There isn't really a scientific way to determine an all-underrated team. Certainly, if you own five fantasy teams, you know all about these guys, but my perception is these players are better than widely believed or haven't yet received the kind of attention you would expect given their value. For some, maybe they have had only one big year; for others, maybe it's because they play in a small market. Regardless, I expect all these guys to be productive regulars again in 2015.
C: Rene Rivera, Rays
You can bet if Tampa Bay trades for a player that he's probably underrated. Rivera has played with the Mariners, Twins and Padres in the majors and spent time in the minors with the Dodgers, Mets and Yankees. Not surprisingly, Rivera is an excellent pitch-framer -- hence, Tampa Bay's desire to get him from the Padres in the Wil Myers trade -- and he hit .252/.319/.432 with San Diego in 2014, good numbers for Petco Park. The question is if the bat was a fluke since it was just 329 plate appearances and Rivera hadn't hit much before that. But catchers are sometimes late bloomers at the plate.
1B: Anthony Rizzo, Cubs
Rizzo is probably the biggest name here, but I would suggest that many fans don't realize how good he was in 2014. He had a higher OBP and slugging percentage than Miguel Cabrera. He had a higher FanGraphs WAR than Jose Abreu of the crosstown White Sox but certainly didn't get the same level of national attention. He finished behind Adrian Gonzalez in the MVP voting because he didn't drive in as many runs. He has more power than Freddie Freeman, a young first baseman who gets more recognition. The best part: He's just 25.
2B: Brian Dozier, Twins
Dozier came up as a shortstop in 2012 but has moved over to second base and gets lost among all the quality second basemen in the American League (playing on the Twins doesn't help), but what a season he had: 23 home runs, 57 extra-base hits, 89 walks, 21 stolen bases, solid defense and 112 runs scored, second in the majors behind Mike Trout. Dozier will continue to be underrated in part because he hit just .242, but he still had a higher OBP than Chase Utley, Dustin Pedroia and Ian Kinsler.
3B: Kyle Seager, Mariners
Seager was never a highly rated prospect coming up through the Mariners system -- projected as a utility infielder -- so sometimes it takes a few years for everyone to buy into a player like that. Well, the Mariners have bought in, giving Seager a seven-year, $100 million contract extension. He made his first All-Star team in 2014 and won a Gold Glove, and his 25 home runs and 96 RBIs are even more impressive considering the difficult hitting environments of the AL West.
SS: Jhonny Peralta, Cardinals
It's odd for a veteran like Peralta to make a list like this, but he has always been underappreciated -- although I did sense a little more, "Oh, yeah, that guy's pretty good," in 2014 as he even picked up some down-the-ballot MVP votes for the first time in his career. Maybe playing for the Cardinals helped. He led all major league shortstops in WAR in 2014, ranking 15th among all position players on Baseball Reference and 17th on FanGraphs. The key is that Peralta has always been viewed as a shortstop without a lot of range, but the metrics have consistently rated him about average (and a little above in 2014). He has a strong arm and makes few mistakes.
LF: Corey Dickerson, Rockies
Charlie Blackmon was the Rockies outfielder who made the All-Star team in 2014, but Dickerson is the one to watch moving forward. He hit .312/.364/.567 with 24 home runs in 478 plate appearances, and that's not just a Coors-inflated line. He is slated to play left field this year with Carlos Gonzalez moving over to right. The Rockies platooned Dickerson last year, but he deserves the chance to see if he can hold his own against left-handers.
CF: Juan Lagares, Mets
Lagares has certainly received recognition as perhaps the best defensive center fielder in the majors -- winning his first Gold Glove in 2014 -- but because he's not a big basher at the plate, he still seems undervalued overall. And he's not a zero on offense. He hit .281/.321/.382, nothing great, but that makes him about a league average hitter. Baseball Info Solutions credited him with 28 defensive runs saved in 2014, and some speculated that maybe he's not that good. Willie Mays, for example, peaked (under a different system for evaluating) at 21 runs, according to Baseball Reference. Consider this, however: Lagares made 2.85 plays per nine innings in 2014, compared to the league average of 2.48 for center fielders. That's 0.37 more plays per game, which adds up to 49 additional outs over 1,200 innings; Mays' career-best was 0.27 more plays per game.
RF: Kole Calhoun, Angels
Like others on this list, Calhoun was never a top prospect. But all he has done is hit. In his first full season, he hit .272/.325/.450 with 17 home runs and 31 doubles while scoring 90 runs in 127 games. He should have another strong year as the Angels' leadoff hitter.
UT: Ben Zobrist, A's
If there's a captain on the all-underrated team, this guy is it. He does all those things that maybe aren't flashy. He draws walks, hits for some power, plays good defense (at multiple positions) and is durable. Since his breakout season in 2009, he is third among position players in Baseball Reference WAR behind Robinson Cano and Cabrera (second behind Cabrera on FanGraphs).
SP: Doug Fister, Nationals
I've written about Fister enough that maybe he's no longer underrated. He doesn't get a lot of attention pitching in the same rotation as Stephen Strasburg and Jordan Zimmermann, but he's nearly their equal.
SP: Dallas Keuchel, Astros
After getting punched around his first two seasons in the majors, Keuchel looked like a lefty without enough fastball to succeed at the big league level. But he put everything together in 2014, going 12-9 with a 2.93 ERA. I don't think it was a fluke.
SP: Jose Quintana, White Sox
The White Sox rotation goes deeper than Chris Sale and now Jeff Samardzija. Quintana has been one of the best starters in the AL the past two seasons, throwing 200 innings both years with ERAs of 3.51 and 3.32 in a park where fly balls really fly. There's nothing too fancy about Quintana, but he has a complete repertoire of pitches with a curveball, changeup and slider and knows how to pitch.
SP: Hyun-jin Ryu, Dodgers
Similar to Quintana, Ryu is another lefty with a full arsenal of pitches. Ryu throws strikes and limits home runs -- just 23 in 344 career innings in the majors. He missed some time late last year but returned to throw a strong game in the division series. The next step for him is to get up to 200 innings and prove he can be more of a workhorse behind Clayton Kershaw and Zack Greinke.
SP: Alex Cobb, Rays
With David Price gone, Cobb is now the undisputed ace of the Tampa Bay staff. Like Ryu, he just needs to remain healthy, as he has made 22 and 27 starts the past two seasons, although he posted a sub-3.00 ERA both years. With Cobb leading the way, Tampa Bay's young rotation is a good reason why the Rays could be the sleeper team to watch in 2015.
RP: Steve Cishek, Marlins
The sidearmer doesn't blow you away like many closers, but there's no questioning his effectiveness. In four seasons in the majors he owns a 2.65 ERA and has allowed just 10 home runs in 257 2/3 innings as he rarely throws anything above the knees.
RP: Tony Watson, Pirates
Our lefty reliever has put together back-to-back solid seasons with the Pirates, going 10-2 with a 1.63 ERA in 2014 (and making the All-Star team). Lacking command when he first reached the majors, Watson walked just 1.7 batters per nine innings last season while setting a career high in strikeout rate. With a fastball that averages 94 mph, he's a power lefty who could end up a closer someday.