The young lion had too much for the old warrior.
Try as Shane Mosley did, the 40-year-old was no match for 21-year-old Saul "Canelo" Alvarez, who dominated the former world champion and easily retained his WBC junior middleweight title Saturday at the MGM Grand Garden.
Alvarez, who improved to 40-0-1 with an impressive 12-round unanimous decision, was too quick and strong for Mosley, who absorbed considerable punishment, yet remained on his feet to avoid being knocked out for the first time.
That was small consolation to Mosley, who wouldn't say if the fight marked the end of his Hall of Fame career. But it was clear he was giving it serious consideration after his record fell to 46-8-1.
"When the kids start to beat you up ... I gave it all I got. I got beat by the better man tonight," Mosley said.
Alvarez, a 6-1 favorite at the MGM Grand, had a big edge on all of the judges' cards: 119-109 by Glenn Trowbridge and C.J. Ross and 118-110 by Jesse Reyes.
"This was a huge night for me," Alvarez said. "It was a great experience, and I want to thank Shane for giving me this experience. He's a true champion."
Mosley tried to start fast and keep Alvarez off balance. Alvarez quickly figured things out and was constantly on the attack, beating Mosley to the punch.
A cut over the corner of Alvarez's left eye in the third round from an accidental head butt caused brief concern for his corner. But he was undeterred and tried to take Mosley out, hurting him in the fifth and seventh rounds.
"I tried to knock him out, but it didn't work," Alvarez said. "The cut was a new experience, but I didn't let it bother me."
Mosley didn't have the strength to hurt the young Mexican champion or the reflexes to avoid getting hit. Only his vast experience allowed him to stay upright.
"I didn't think he was that fast," Mosley said. "He definitely was very good. He can go a long way."
Alvarez made $1.2 million, and Mosley got $650,000.
Also on the undercard, Las Vegas welterweight Jessie Vargas improved to 19-0 with a 10-round unanimous decision over Steve Forbes. Vargas was unable to hurt him, but Forbes did little to press the attack and Vargas outpointed him on every card. Judge Adalaide Byrd scored it 100-90, Ricardo Ocasio had it 98-92, and Dick Houck scored it 97-93.
"I showed my boxing skills," Vargas said. "I was in there with a veteran and I totally outboxed him. We showed we can box any style."
Former champ Carlos Quintana unleashed a devastating overhand left to the head of DeAndre Latimore and knocked him out at 2:19 of the sixth round in their NABO super welterweight title bout.
Contact reporter Steve Carp at email@example.com or 702-387-2913. Follow him on Twitter: @stevecarprj.