For round after round, it looked like the professor was finally being surpassed by an eager student, as Juan Manuel Marquez looked his age and Juan Diaz outworked the Hall of Fame-bound hitter in the main event at the Toyota Center in Houston, Texas on Saturday night. Diaz, age 25, soaked in the cheers in his hometown and channeled their adulation as he forced the 35-year-old Marquez to work as hard as he’s ever had to work, and battered him time and again on the ropes.

But the professor showed the student why he’s regarded as one of the top two or three fighters, pound for pound, in the game today, as he turned the tide in the ninth round, scored a knockdown, and then came in for the kill. Marquez, not yet ready to cede his position of power to the next generation, finished off Diaz with a right uppercut at 2:40 of the ninth in a fight that will be in contention for Fight of the Year come December.

Marquez (age 35; 134 ¼ pounds; 49-4-1, with 36 KOs entering; from Mexico) met the IBO lightweight champion Diaz (age 25; 134 ½ pounds;  34-1, with 17 KOs entering; from Houston), and put his Ring crown up for grabs in the HBO televised affair. The vacant WBO and WBA belts were also there for the taking.

In the first round, both men got down to business ASAP. Nobody in boxing places punches better than Marquez, but Diaz didn’t want to hear it. He thought coming in Marquez starts slowly, and he was hellbent on making an impression from second one. There were several rousing trades in the first, and both men made a claim for the round.

In the second, Diaz hurt Marquez with a hook. JMM didn’t clinch, or run, he blasted back. Was Diaz going to be the stronger hitter, even though his power is questioned? In the third, Marquez moved more, smartly. Diaz scored when he had him against the ropes, but he tasted leather too. In the fourth, Diaz landed that left hook again, and again trapped JMM on the ropes. He told the judges that he didn’t care if JMM came in with the bigger rep, and had fought a bunch of Hall of Fame-bound fighters. Diaz was making his case that though he wasn’t born in Mexico, like JMM, he wants Mexican fight fans to hop onto his bandwagon, as they search for replacement icons for Erik Morales, Marco Antonio Barrera and perhaps Antonio Margarito. Announcers Jim Lampley, Manny Steward and Max Kellerman wisely let the action speak for itself for long stretches.  It looked to TSS that JMM, if he didn’t exactly get old overnight, was looking a lot closer to 35 than 25, as we’d seen in recent years.

In the fifth, Diaz got nailed in center ring. But he didn’t seem bothered by featherweight level power. And of course he kept bulling JMM to the ropes, where he got to work. Blood trickled from Marquez’ right eye, which has been a persistent problem area, and he asked trainer Nacho Beristain after the round if he was ahead. If you have to ask, son, you know the answer ain’t yes…

In round six, Diaz’ straight ahead style again told the judges that he was the offensive dynamo in this scrap. Marquez backed up, and pecked, and countered, not a style to sway the judges. But then he’d fight strong off the ropes, making the round harder to call. In the seventh, JMM stayed off the ropes early. But his legs looked 35 plus, and he needed them to deliver him to safer ground, away from the busy Diaz. The Texan’s volume had dropped off some by this point, but Marquez didn’t look fresh as a daisy.

In the eighth round, a left uppercut opened a cut on Diaz’ right eye. The elder wasn’t planning on fading away, clearly. He wasn’t backing up so much, and he hurt Diaz with a left hook. His legs faltered, but he caught himself, and soldiered on, as blood from his eyelid obscured his vision. The tide had turned, in favor of the sharpshooting vet. In the ninth, JMM was up off his stool early, eyeing the younger man with a big cat’s cool. But Diaz’ energy spiked. He backed him up again, imposed his strength and willpower on JMM. Then Marquez put together a nasty combo, and dropped him with under a minute to go. A right sent him face first onto the bottom rope. He bounced up, and took an eight count. Marquez was on him, and ripped in with an assassin’s cool. A right uppercut sent him down, and out. The ref didn’t even count, as Diaz lay on his back, unable to summon the power to even try and rise.

JMM went 288-732, while Diaz was 252-781 according to Punchstat.

Marquez told Max Kellerman after that with head and body movement, he was able to steer clear of enough Diaz' throws to take him into deep water. Around the fifth round, JMM said, he noticed that punches to the body were hurting Diaz. In the near future, JMM said he'll go up in weight, and that he wants to fight Floyd Mayweather, for pound for pound supremacy. Diaz told Max that “I got caught with a good punch” and said that blood in his eye bothered him badly. “I kept fighting my heart out, he caught me with a good punch, what can I say?” He said that his fighter's instinct forced him to bang away, rather than clinch, when he was hurt.

For the record, judges Max DeLuca had Diaz up 77-75, Duane Ford had Marquez winning 77-75, and Levi Martinez saw it 76-76 after eight rounds were in the bag.