Five key fights: Floyd Mayweather Jr.

Pro fight No. 18
Opponent: Genaro Hernandez (38-1-1)

Date: Oct. 3, 1998, Las Vegas
Result: Mayweather by TKO in 8

Why it matters: It's unfortunate that a great fighter such as Genaro Hernandez was merely a trial horse for both Mayweather and Oscar De La Hoya early in their careers, but both young stars went through him as they broke into boxing's major league, and they were Hernandez's only two losses.

Mayweather was 17-0 and challenging for his first world title belt (WBC super featherweight) when he got to "El Chicanito." At 21, Floyd had established himself as a boxer-puncher whose dazzling hand speed enhanced the force behind his fists. In his previous fight, against 6-foot-1 Tony Pep, Mayweather landed almost 200 more punches than his opponent over 10 rounds.

Halfway into the first round, Mayweather fell in his corner while backing away from a Hernandez rush, but it was ruled a slip. After that, his speed and skills began to emerge. He seemed to land two punches for every one from Hernandez, coming from multiple angles with hard jabs, left hooks, straight rights and uppercuts.

Hernandez was backed against the ropes for stretches of Round 5 while Mayweather targeted openings, and a hard right uppercut rattled Hernandez's jaw. In the sixth, Hernandez tried luring Mayweather into traps, but the traps never sprung. In the seventh, he tried to bull forward, his head in Mayweather's chest. But when they went toe-to-toe, Floyd was faster on the inside, too, with hard, short hooks and uppercuts.

Hernandez's corner -- led by his brother-trainer Rudy -- seemed prepared to give its fighter just one more round to turn things around after the seventh. He didn't. Mayweather just kept beating him up, and after the eighth, the champion's corner threw in the towel.

Mayweather had been so cocky before this fight that he prematurely wore a WBC championship patch on his trunks into the ring. Overcome by emotion after the actual victory, he sank to a knee and cried. Hernandez, 32, would never fight again.

Pro fight No. 25
Opponent: Diego Corrales (33-0)
Date: Jan. 20, 2001, Las Vegas
Result: Mayweather by TKO in 10

Why it matters: This showed just how devastating Mayweather can be when he is on. He dismantled a world-class, undefeated tough guy. At various times during this spectacle, the TV announcers compared Mayweather to Sugar Ray Leonard, Pernell Whitaker, Willie Pep, Muhammad Ali -- and Tiger Woods.

Corrales thought he could succeed by getting Mayweather to "stop and fight," but he never had a plan for making that happen. He disastrously walked forward without jabbing or threatening Mayweather, while holding his hands too low to stop Mayweather's blasts. Mayweather made Corrales miss and came back with jabs, right-hand leads and an explosive left hook that lasered in on Corrales' body and head.

After the opening bell of Round 7, Mayweather connected with a left hook that scored the fight's first knockdown -- and he unleashed two more left hooks before Corrales hit the floor. Another mammoth left hook put Corrales down later in the round, and a barrage in the corner put Corrales down a third time. In that insane seventh round, Mayweather connected with 78 percent of his shots -- 39 out of 50. Corrales threw five punches and landed three.

Corrales landed a couple of punches in the eighth, causing Mayweather to smile, but Corrales never put multiple blows together. Mayweather began to land almost freely from midrange. Midway through the 10th, Mayweather, while backing up, caught Corrales with a tight left hook and sent him down again, and not long after that, a straight right banged a wobbly Corrales to a knee, down for the fifth time. Over the objection of a beaten but still lucid Corrales, his father-trainer threw in the towel. Corrales choked back tears over the stoppage in a postfight interview; he'd wanted the chance to either score a Hail Mary knockout or go out on his back.

But he'd been crushed. In no round did Corrales land as many as 10 punches, and in the end, his 29 percent connect rate (Mayweather was at 53) looked better on paper than in combat.

"It was just my night," Mayweather said afterward.

"Well, most nights are your night," responded TV interviewer Larry Merchant.

Pro fight No. 28
Opponent: Jose Luis Castillo (45-4-1)
Date: April 20, 2002, Las Vegas
Result: Mayweather by decision in 12

Why it matters: A lot of people believe this was Mayweather's only loss, although the three official judges who awarded him a unanimous decision are the ones who mattered, and Mayweather went to 28-0. Still, the way Castillo pressured and slowed Mayweather might be mankind's only blueprint for how to beat him, and many experts believe De La Hoya's only chance May 5 will be to take a similar tack.

With little chance to outbox Mayweather in the center of the ring, Castillo did his best to force Mayweather to the ropes, where Mayweather wouldn't be able to jump or lean far back to avoid blows. Against the ropes is where punchers Jesus Chavez and Gregorio Vargas had succeeded in landing head shots on Mayweather, threading shots through the two flanks of his upstairs defense: a shrugged left shoulder and a right glove held close to the cheek.

Castillo began his attack in Round 4, charging in low and aiming body shots, moving well to remain a more elusive target than Corrales had been. Mayweather landed uppercuts and other shots as Castillo advanced, and they clinched often, but Castillo kept coming. By the seventh, it became a cat-and-mouse game: Castillo pressing Mayweather back to the ropes, Mayweather dancing and punching to escape, trying to keep the action in the middle in the ring. It got rough. Each fighter was penalized a point in the late rounds for a foul.

By the 12th round, Castillo was still slugging and seemed to have scored the more effective blows. In total, he landed 107 more "power" (nonjab) punches than Mayweather. But the judges gave a lopsided scoring decision to Mayweather.

"Not the fight we saw," announcer Jim Lampley complained.

Mayweather claimed afterward that he had fought with "a messed-up arm" and two broken ribs. Then he beat Castillo more decisively in their rematch eight months later.

Pro fight No. 34
Opponent: Arturo Gatti (39-6)
Date: June 25, 2005, Atlantic City
Result: Mayweather by TKO in 6

Why it matters: This is the fight that showcased Mayweather for the sports universe beyond hard-core boxing fans and set him up as a pay-per-view brand name, which to him was a more important career step than winning the WBC junior welterweight championship he took from Gatti. And how forcefully it showed Mayweather off, as he pounded the overmatched New Jersey hero into mincemeat.

Gatti and trainer Buddy McGirt had a plan for this fight. Gatti came out in Round 1 jabbing carefully, feinting, staying at a distance. The slugger had become a boxer! But then what clearly appeared to be a referee's error took Gatti out of the game. With Mayweather pushing Gatti's head down in a clinch near the end of the round, ref Earl Morton yelled "Stop punching!" to order the fighters to break. But he didn't step between them, and as Gatti was stepping back, Mayweather cracked him in the cheek with a left hook. As Gatti turned to the referee to complain that Mayweather hitting on the break, Mayweather unloaded an even bigger left hook to Gatti's temple that put him down. It was scored as a knockdown despite Gatti's argument to Morton that "This is bulls---!"

In the corner, McGirt implored Gatti: "Don't let that take you off your game plan." But it did.

Gatti started trying to land bigger, swinging shots, and he stiffened up defensively. Mayweather began beating Gatti to punches and combinations from all kinds of angles. As early as Round 4, there was reason to wonder what was holding Gatti up. One brutal sequence from Mayweather went straight right, left hook, straight right, left hook, straight right, before Gatti could move his head out of the way. Mayweather's body shots did just as much damage.

After Round 6, with Gatti's face reddened and eyes swollen to slits, McGirt stopped the fight. Gatti had landed 17 percent of his punches, compared with 57 for Mayweather. Once again turning to innocent, Mayweather sank to his knees and cried, as visions of seven-figure paydays surely danced in his head.

Pro fight No. 37
Opponent: Carlos Baldomir (43-9-6)
Date: Oct. 11, 2006, Las Vegas
Result: Mayweather by decision in 12

Why it matters: Mayweather's winning title fight against Carlos Baldomir -- his last fight before going against De La Hoya -- was considered more than just a made-for-pay-TV match, as the Gatti destruction has been. After all, Argentine veteran Baldomir had dominated Gatti just as thoroughly as Mayweather had, and Baldomir also had taken the undisputed welterweight crown from Zab Judah, making him true heir to a title held previously by Hall of Famers such as Sugar Ray Leonard, Emile Griffith and Sugar Ray Robinson.

Baldomir also had conquered speed. Judah is as fast as Mayweather, and Baldomir walked through Judah's artillery like Al Pacino in the climactic shootout scene of "Scarface."

Baldomir came out with a style that has brought some of history's better performances against Mayweather -- and that might need to be part of De La Hoya's playbook. He walked forward and crowded Mayweather, rushing forward, clinching, banging punches on the inside, trying to force Mayweather back to the ropes. Mayweather was able to stay nimble, though. Sticking and moving, he made Baldomir look even slower than he was, making him miss punches badly, then landing counter shots. Even when cornering Mayweather, Baldomir wasn't punching crisply, just swinging his arms robotically, almost pawing.

Mayweather did just enough to win every round. But what Baldomir did was take Mayweather the distance and expose his lack of interest in scoring knockouts. With his tender hands, Mayweather has become content to let fights play out and cruise to decisions -- six of his past 10 bouts have gone the distance. He can't be considered a knockout artist anymore.

Don Steinberg, a winner of the Boxing Writers Association of America's award for best column in 2005, covers boxing for The Philadelphia Inquirer.