Alabama looks unbeatable this season, as evidenced by it being a two-touchdown favorite at No. 3 LSU this week, but there have been plenty of instances when an athlete or team had the aura of invincibility, only to suffer a shocking defeat.
We look at some of the most notable upsets in recent sports history.
NFL
2007 New England Patriots
Unbeatable résumé: The Patriots tore through the NFL in 2007, winning all 16 regular-season games (12 by double digits) and scoring a then-NFL record 589 points. New England dispatched the Jacksonville Jaguars and San Diego Chargers in the playoffs to set up a Super Bowl XLII rematch with the New York Giants, a wild-card team that the Patriots defeated in the season finale.
The upset: The Giants came in as 12-point underdogs but used a relentless pass rush to hold the Patriots' offense to a mere two touchdowns. That allowed the Giants a chance to drive toward the game-winning score with 35 seconds left -- helped by a miracle helmet catch by David Tyree -- and pull off a 17-14 upset, denying New England its perfect season.
Unbeatable quote: "It was a month before I really felt back to myself. It was a nightmare. You woke up the next morning -- I said, 'It didn't happen. There's no way it happened.'" -- Patriots QB Tom Brady
1998 Minnesota Vikings
Unbeatable résumé: With a potent offense led by quarterback Randall Cunningham, Pro Bowl receiver Cris Carter and rookie phenom Randy Moss, the Vikings scored 556 points en route to a 15-1 record. Minnesota had a nine-game winning streak entering the NFC Championship Game against the Atlanta Falcons at home.
The upset: The Vikings looked to be safely on their way to Super Bowl XXXIII, as they had a 27-20 lead and had Gary Anderson, who hadn't missed a field goal all season, set up for a 39-yarder with 2:11 left. But Anderson missed it wide left, the Falcons drove down the field to score a tying touchdown and hit a game-winning kick of their own in overtime to head to the Super Bowl.
Unbeatable quote: "I took tremendous pride throughout my career about being the one guy on the team that everyone could count on in a crucial time, and that time, that particular kick, I missed the kick. So, yeah, that was certainly a difficult thing to deal with." -- Anderson.
2001 St. Louis Rams
Unbeatable résumé: "The Greatest Show on Turf" looked like a cinch to win its second Super Bowl championship in three years, as Kurt Warner, Marshall Faulk & Co. blitzed to a 14-2 regular-season record and playoff victories over the Green Bay Packers and Philadelphia Eagles. The Rams were 13.5-point favorites over the upstart Patriots in Super Bowl XXXVI.
The upset: The Patriots were given no shot, but New England's defensive scheme flummoxed the Rams, leading to the Pats' 17-3 edge entering the fourth quarter. The Rams tied the game 17-17 on a 26-yard touchdown pass from Warner to Ricky Proehl with 1:30 left, but Tom Brady led a game-winning drive to set up a 48-yard Adam Vinatieri field goal as time expired.
Unbeatable quote: "For a long time, it hurt really bad. ... Now that I'm a bit older and you gain more perspective, I'm just fortunate that I got to play in that game. It was the start of Tom Brady's career." -- Warner
College basketball
1991 UNLV Runnin' Rebels
Unbeatable résumé: After crushing Duke by 30 points to win the 1990 national championship, a loaded UNLV team featuring future NBA stars Larry Johnson and Stacey Augmon looked to be on pace for a repeat, as the Running Rebels ripped off a perfect 34-0 record heading into a national semifinal rematch with Duke, a game in which they were heavily favored.
The upset: It was clear from the beginning there wouldn't be a repeat of the '90 title game, as Duke raced out to a 13-5 lead. UNLV retook the lead but was unable to shake the Blue Devils, who got their revenge when Christian Laettner hit a pair of free throws with 12.7 seconds left to give Duke the 79-77 win. Duke won its first national championship two nights later.
Unbeatable quote: "Sometimes, we players lose sight of the fact we had a great season. ... I think a lot of what we accomplished got lost in the fact that we didn't go undefeated." -- former UNLV point guard Greg Anthony
2015 Kentucky Wildcats
Unbeatable résumé: John Calipari's group of five-stars rolled into the Final Four looking like a good bet to be the first undefeated men's basketball team since the 1976 Indiana team, as Karl-Anthony Towns & Co. rolled to a 38-0 record heading into their national semifinal matchup with Wisconsin. They weren't shy about embracing their desire to be perfect.
The upset: The Badgers were defeated by Kentucky in the Final Four the year before and fell behind the Wildcats by four points with 6:37 to go. Wisconsin flipped it on Calipari's squad, ripping off a 15-4 run from that point to eliminate the Wildcats 71-64 and deny them the chance at a 40-0 season.
Unbeatable quote: "I think we were either down four or six with some seconds left or a minute left and, you know, it was a terrible feeling. ... I just started crying, actually, on the sideline. I just really don't know how to explain it." -- Kentucky guard Tyler Ulis.
1999 Duke Blue Devils
Unbeatable résumé: Although Duke had one loss -- on a buzzer-beater versus Cincinnati in late November -- it was looking to be arguably the most dominant team in the modern era. Duke became the first team in ACC history to go 16-0, winning all but one of those games by double figures. Heading into the national final, the Blue Devils had won 32 straight and their average margin of victory in their five NCAA tournament games was a whopping 25.2 points. Duke cutting the nets down was all but a certainty.
The upset: Duke faced Connecticut in the final, and although the Huskies were a No. 1 seed in the NCAA tournament, not many expected them to challenge the Blue Devils, who had four players taken in the top 14 of the NBA draft in 1999. But UConn, which entered as a 9.5-point underdog, got clutch play from point guard Khalid El-Amin and Richard Hamilton, who had a game-high 27 points. The Huskies shot 51.7 percent from the field and pulled off the stunner 77-74.
Unbeatable quote: Duke had relied heavily on sharpshooter Trajan Langdon all season, but the senior was unable to come through on the final two possessions. He was called for traveling on Duke's next-to-last possession, then stumbled and failed to get off a tying 3-pointer in the final 5.2 seconds. "I tried to get off a shot but I got tripped up a little. [The ball] was stripped," Langdon said. "It was a [clean] strip. Everything about the game was clean. We got beat."
NBA
2015-16 Golden State Warriors
Unbeatable résumé: The Warriors set an NBA record for wins, going 73-9 thanks to Steph Curry, Klay Thompson and Draymond Green leading the way. Curry won his second straight MVP award and the Dubs were in discussion with the 1995-96 72-win Chicago Bulls as the best NBA team -- ever.
The upset: Golden State went up 3-1 in the NBA Finals against the Cleveland Cavaliers and LeBron James -- and then infamously blew said lead. While the Warriors were heavy favorites, they lost Green for Game 5 and ultimately were undone by the prowess of James and Kyrie Irving.
Unbeatable quote: "One of the most brutal things I've ever had to go through in my life. If I played, we win of course, so I do feel it's my fault that we lost. Absolutely my fault." -- Draymond Green
2010-11 Miami Heat
Unbeatable résumé: The Big Three. The Heatles. Utter dominance -- that's what was expected when LeBron James, Dwyane Wade and Chris Bosh joined forces in Miami. These were three of the best players, teaming up in South Beach.
The upset: Well, they made it to the NBA Finals, but not much more. After a rocky start to the season, the Heat righted the ship and entered the Finals as a favorite against the Dallas Mavericks. But they couldn't stop Dirk Nowitzki, Jason Kidd & Co., and fell in six games to a worthy opponent.
Unbeatable quote: "All I remember is telling those guys that they deserved it. Hands down, they were the better team in this series. ... All we can do is just admit it and move forward." -- Chris Bosh
2003-04 Los Angeles Lakers
Unbeatable résumé: Two future Hall-of-Famers (Karl Malone and Gary Payton) teaming up with two other future Hall-of-Famers (Shaq and Kobe) in L.A.? What could go wrong?
The upset: Like other deep, talented NBA teams, this Lakers squad made it to the Finals. But they were no match for the deeper, defensive-minded Detroit Pistons. In a shocking upset, the Pistons emerged as the better team, (Malone and Payton were at the ends of their careers) and won the series in five games.
Unbeatable quote: "Talent doesn't get it done. You have to be able to execute. When you have talent and you execute, that's when you win." -- Kobe Bryant
College football
2002 Miami Hurricanes
Unbeatable résumé: The Hurricanes had laid waste to the competition en route to the 2001 national championship and followed that up by compiling a 12-0 record in 2002. Miami's winning streak heading into the BCS National Championship Game with No. 2 Ohio State at the Fiesta Bowl, which dated back to September 2000, was 34 games.
The upset: The Hurricanes were 12-point favorites to beat the Buckeyes. Ohio State was spunky though, forcing Miami to kick a field goal to force overtime. Miami scored a touchdown in the first overtime and looked like it had stopped the Buckeyes on their overtime possession, but a late whistle for pass interference on Glenn Sharpe kept Ohio State alive. The Buckeyes tied the game after the penalty, scored a touchdown in the second OT and stopped Miami for an improbable 31-24 victory.
Unbeatable quote: "It feels unreal. ... After the game was over, it felt like we had one play left. It can't be over. It's something I never want to feel again." -- Miami fullback Quadtrine Hill.
2005 USC Trojans
Unbeatable résumé: The Trojans went undefeated in the regular season as they looked to repeat as national champions. Matt Leinart, Reggie Bush & Co. easily defeated crosstown rival No. 11 UCLA 66-19, before heading to the BCS National Championship Game at the Rose Bowl with a No. 1 ranking.
The upset: After a back-and-forth battle, Vince Young and No. 2 Texas went ahead for good with 19 seconds left in the game to end USC's 34-game winning streak and deny the Trojans an unprecedented third straight national championship. The Longhorns were a unanimous No. 1 in the final Associated Press Top 25 and won the BCS title.
Unbeatable quote: "I still think we're a better football team. They just made the plays in the end." -- USC quarterback Matt Leinart
Boxing
Mike Tyson
Unbeatable résumé: Mike Tyson was a household name at 20 years old -- he even had a Nintendo video game featuring him. Not hard to see why. Tyson became the youngest heavyweight champion in boxing history at 20 when he flattened Trevor Berbick in 1986. Tyson won his first 37 pro fights, with 33 coming via knockout, and made nine title defenses. Dressed in his customary black trunks, Tyson appeared to be the most intimidating athlete in the world.
The upset: Talk about your all-time mismatch, Tyson closed as an unfathomable 42-1 favorite against challenger James "Buster" Douglas on Feb. 11, 1990, at the Tokyo Dome. A Tyson win was such a no-brainer that only one Las Vegas casino -- The Mirage -- was taking action on the outcome of the contest, which was supposed to be a tune-up for a mega-fight with Evander Holyfield later in the year. But Buster refused to be bullied, clocking Tyson unlike anyone ever had and sent him to the mat in the 10th round. Referee Octavio Meyran counted to 10, marking arguably the greatest upset in sports history.
Unbeatable quote: Tyson reportedly slacked off in training before his fight with Douglas. Even his cornermen -- Tyson dumped longtime trainer Kevin Rooney in favor of Aaron Snowell and Jay Bright -- apparently felt that victory was a sure thing, inexplicably failing to pack an ice bag. One would have come in handy midway through the fight, with Tyson's left eye beginning to swell shut. "Nobody could beat Tyson but himself, and he beat himself," Tyson's promoter, Don King, told ESPN.com in 2015. "He was so unbeatable, and everyone believed that and supported that theory that he strayed away from what had made him champion. He fell short there because he began to believe his own headlines. He took this guy lightly."
MMA
Ronda Rousey
Unbeatable résumé: Calling Ronda Rousey the "baddest woman on the planet" was by no means a stretch. Blink, and you practically missed all of her fights. Rousey was 12-0 overall and won her first six fights in the UFC. She had been taken past the first round just once in her career, and had a four-fight stretch in the UFC where she finished her foes in an average of 32.5 seconds. Really, who was going to stop "Rowdy" Ronda?
The upset: After six consecutive title defenses -- she was crowned the women's bantamweight champion upon signing with the UFC in 2012 -- Rousey was set to face Holly Holm on Nov. 14, 2015. Holm appeared to be the next surefire victim for Rousey, whom one betting site had as high as a 20-1 favorite on fight night. But the 56,000-plus fans -- a UFC record attendance -- at Etihad Stadium in Melbourne, Australia, got far more than they expected. Rousey, whose bread and butter was her armbar submission, decided to trade blows with Holm, a former boxing and kickboxing champion. And boy, did Rousey pay. She lost a round for the first time in her career, then Holm delivered a head kick in the second round that rocked the sports world. Holm even earned an ESPY in 2016 for "Upset of the Year."
Unbeatable quote: After the loss, Rousey was taken to a Melbourne hospital and didn't give a postfight interview. In fact, it seemed like ages before she re-entered the public eye. Perhaps longtime UFC color commentator Joe Rogan best summed up Rousey's stunning defeat just seconds after it happened during the pay-per-view broadcast. "Oh. My. God. Unbelievable."
Olympics
Aleksandr Karelin, 2000 Olympics
Unbeatable résumé: Karelin wasn't only a legendary wrestler in the super-heavyweight class, but he was an icon in the sport. The Russian had won three consecutive gold medals in Greco-Roman wrestling coming into Sydney 2000, hadn't lost a match in 13 years and hadn't conceded a point in six years. A fourth gold seemed to be a formality heading into the final match with Rulon Gardner.
The upset: Gardner had never finished higher than fifth in the world and had lost to Karelin in a prior match, but he was able to get through the first period in a scoreless tie. He then was able to score a point when he escaped Karelin's grasp in the second period. Karelin was never able to get a takedown on Gardner, who won 1-0 for an unlikely gold.
Unbeatable quote: "In the last seconds, he mumbled something in Russian. I think it was basically, 'I give up. I give up.'" -- Gardner
2004 U.S. men's basketball
Unbeatable résumé: Led by Hall of Fame coach Larry Brown (with Gregg Popovich and Roy Williams serving as assistants), Team USA featured the two most recent NBA MVP's in Tim Duncan and Allen Iverson on a squad that also included LeBron James, Dwyane Wade and Carmelo Anthony. The U.S. national team had suffered only two Olympic losses in its history heading into the 2004 competition.
The upset: Which one? Team USA suffered its biggest defeat in Olympic competition in Game 1 of group play, a 92-73 loss to Puerto Rico. The U.S. lost in Game 4 to Lithuania (94-90) and again in the semis to Argentina (89-81) and had to settle for a bronze medal. The three losses were more than the previous 14 competitions combined.
Unbeatable quote: "The team kind of came together at the last minute. Everyone was trying to cater to Coach Brown's style, which is a little bit different to what they would've wanted. Coach Brown didn't really like to play young guys. At all. Even I think LeBron, D-Wade and Melo didn't play as much. We all played the least, us young guys." -- Emeka Okafor
Soccer
1982 Brazil
Unbeatable résumé: Brazil's team at the 1982 World Cup was incredibly talented and very confident. Led by Zico, who was arguably the best player in the world, Brazil had won all of its qualifying games, defeated host nation Spain and reigning European champion West Germany -- twice.
The upset: Brazil needed only a draw against Italy in the final group game but did not alter its artistic, aesthetically pleasing style of play, feeling it would be able to score at will. A counterattacking Italy team went on to a 3-2 win.
Unbeatable quote: The game against Italy was called "the day football died" by Zico. "We were obviously saddened by the result, but everybody had clear consciences. The Seleção were going home, but we had stood by our convictions till the end. We didn't allow the win-at-any-costs mentality to compromise our belief in the beautiful game."
MLB
2001 Seattle Mariners
Unbeatable résumé: They had a 116-46 record, for starters. The M's led the league in basically every category: runs, hits, on-base percentage, team ERA, batting average against, shutouts, the list goes on. They had a deep lineup that included some rookie named Ichiro.
The upset: Maybe the team was gassed from the record regular-season run. Or maybe the playoffs are just a crapshoot. They went down in the American League Championship Series 4-1 to the New York Yankees.
Unbeatable quote: "It wasn't supposed to end like this. It wasn't supposed to end here." -- Bret Boone, after losing the ALCS to the Yankees
1995 Cleveland Indians
Unbeatable résumé: The Indians had 100 wins in a 144-game regular season, the most ever by an American League team in a season with less than 154 games. Cleveland won the Central Division by 30 games while leading the majors in batting average, home runs, runs scored, hits and RBIs.
The upset: The Indians lost to the Atlanta Braves in the World Series in six games. The Braves had won 90 regular-season games that year.
Unbeatable quote: "This was a good season. The only thing we didn't do this year was win this thing. But we played like champions. I really feel we did." -- Indians manager Mike Hargrove to cleveland.com
1988 Oakland Athletics
Unbeatable résumé: The A's won 104 games on the way to their first of three straight American League championships. Jose Canseco led the AL with 42 home runs and became the first player to hit 40 home runs and steal 40 bases in the same season.
The upset: Heavily favored Oakland lost to the Los Angeles Dodgers in the World Series in five games. The most lasting memory is Kirk Gibson's pinch-hit, walk-off home run off Dennis Eckersley to give the Dodgers the win in Game 1.
Unbeatable quote: "In a seven-game series, one dramatic game change can be the turning point in the series, whenever it comes, especially if it comes late and turns a loss into a win." -- Oakland manager Tony La Russa on the 25th anniversary of Gibson's home run
NHL
1995-96 Detroit Red Wings
Unbeatable résumé: Detroit set a record for the most regular-season wins in NHL history with 62 and had the second-most points ever during the regular season with 131, just one behind the record set by Montreal in 1976-77. The Red Wings scored at least one goal in all of their games and had two nine-game winning streaks during the season. Detroit also allowed the fewest goals and tied Washington for the most shutouts that season.
The upset: After a remarkable regular season, the Red Wings were eliminated by Colorado in six games in the Western Conference finals and failed to make the Stanley Cup Final. The Avalanche went on to win the Stanley Cup in their first year after moving from Quebec and a fierce rivalry was born.
Unbeatable quote: "There's no guys we hated more, but there were no guys we respected more. Without the Colorado Avalanche, the Detroit Red Wings aren't as good and successful as they are, and the other way." -- Red Wings forward Darren McCarty to Sports Illustrated in 2016
Women's basketball
2016-17 UConn Huskies
Unbeatable résumé: The Huskies headed to the Final Four with a perfect 36-0 record and an 111-game winning streak. UConn had won four straight national championships and hadn't lost in 865 days.
The upset: Mississippi State stunned UConn with perhaps the biggest upset in women's basketball history, winning 66-64 on Morgan William's overtime jumper in the national semifinals. Mississippi State and UConn had met in the Sweet 16 the previous season and the Huskies won by 60 points -- the most lopsided win in regional semifinals history.
Unbeatable quote: "Look, nobody's won more than we've won. I understand losing, believe it or not. We haven't lost in a while, but I understand it. I know how to appreciate when other people win." -- UConn coach Geno Auriemma
2017-18 UConn Huskies
Unbeatable résumé: The Huskies were undefeated in the regular season, winning both the AAC regular-season championship and the AAC tournament title. They were 36-0 heading into the Final Four.
The upset: For the second straight year, UConn lost in the national semifinals on a last-second shot in overtime, this time to Notre Dame. Arike Ogunbowale's jumper from the corner with a second left gave the Irish a 91-89 victory and ended the Huskies' 36-game winning streak.
Unbeatable quote: "There's nothing you can say to a college kid after experiencing this two years in a row that's going to make them feel any better about, you know. We had an amazing run for five months. That's just the way it is. One weekend in March gets to decide your season." -- UConn coach Geno Auriemma