Nonito Donaire stopped Toshiaki Nishioka at 1:54 of the ninth round Saturday night, defending his WBO 122-pound title with a dominant performance in his 29th straight victory.
Brandon Rios also stopped Mike Alvarado in the seventh round of a sensational 140-pound bout in the co-main event at a sold-out Home Depot Center. Both previously unbeaten fighters absorbed enormous punishment and rallied tenaciously in what's likely to be considered one of the year's best fights.
Donaire (30-1, 19 KOs) was less thrilling but more dominant, patiently waiting for openings against Nishioka (39-5-3) before knocking down the Japanese veteran in the sixth despite hurting his left hand during the bout.
Donaire, the Filipino-born fighter raised in California's Bay Area, then put him down again with a vicious right hand in the ninth, and referee Raul Caiz stopped it after Donaire landed an uppercut moments later. Nishioka had won 16 straight fights since March 2004, but couldn't keep up with Donaire's combination of power and tactical skill.
Nishioka threw just eight punches in the first round, and the crowd that had just watched Rios' frenzied slugfest with Alvarado understandably booed the early rounds. Donaire attempted to force the action with little success until the sixth, when he landed a left uppercut, followed by a right hand and another uppercut that put Nishioka on the canvas.
Donaire, who also held the IBF version of the 122-pound title before vacating it this week, was upstaged by Rios and Alvarado in a fight that thoroughly lived up to its hype.
Rios (31-0-1, 22 KOs) and Alvarado put on a show for the packed arena, trading hundreds of big shots and largely ignoring defense. Both fighters are known as heavy-handed brawlers, and both stayed on their feet during 6 1/2 rounds of bombardment, starting with a frenetic first round in which both fighters landed numerous devastating blows. The left side of Alvarado's face began to swell, and Rios took damage all over his face.
Rios, the Kansas-raised former lightweight champion, ate dozens of powerful shots from the Denver-based Alvarado (33-1) in the fifth and sixth rounds.
Alvarado threw 147 punches in the fifth round alone — but Rios abruptly landed a devastating overhand right that rendered his opponent defenseless in the seventh. Alvarado took several additional shots before referee Pat Russell stepped in with Alvarado backed against the ropes.
"It was a really tough fight, but I could have gone a little longer," Rios said. "He tested my chin, and I handled it. I am a warrior. He didn't hurt me. He got me a little stunned, but I was ready to go on."
Alvarado threw 238 more punches than Rios, but the winner connected with a much larger percentage of total blows. Rios landed 33 percent of his 440 power punches, while Alvarado connected with 31 percent.
Alvarado thought Russell had stopped the fight too early, but complimented Rios' toughness.
"He shook me up a little bit, but I could have kept fighting," Alvarado said.
Top Rank promoter Bob Arum had said the winner of this bout would be considered as Manny Pacquiao's next opponent, but both Rios and Alvarado said they were open to a rematch.