Nonito Donaire knocks down Toshioka Nishioka with a punch in the sixth round… (Harry How / Getty Images )
Brandon Rios and Mike Alvarado engaged in a fight-of-the-year slugfest at Home Depot Center on Saturday night, with Oxnard's Rios notching a seventh-round technical knockout that proves he retains wallop while moving up in weight.
Nonito Donaire couldn't match the nonstop brawling of that bout, but he did take another step toward standing as the world's top super-bantamweight with a ninth-round technical knockout of Japan's Toshiaki Nishioka.
Former lightweight champion Rios, in his junior-welterweight debut, unleashed a pair of hard overhand rights in the seventh, then pounded two lefts onto Alvarado's mug to force referee Pat Russell to stop the fight at the 1:57 mark.
"Maybe it could've gone a little longer, a little more time, but he was ready to drop," Oxnard's Rios (31-0-1, 22 knockouts) said of the technical knockout.
Alvarado (33-1) complained he "could've fought through it," and was "surprised" by Russell's stoppage.
After instituting a strategy to fight behind his jab and stand inside and brawl with Rios as the naturally bigger man, Alvarado was every bit Rios' equal through six rounds.
Rios was marked under the right eye, and often got the worse of exchanges that drew roaring cheers from the 7,665 in attendance.
Rios admitted he was hurt at times, "but I didn't show it, and kept on doing my thing."
Two judges had the bout scored 57-57, with the other giving Rios a 58-56 edge.
But Rios rocked Alvarado's jaw with the rights in the seventh, causing Alvarado to reel back to the ropes while Russell peered in, clearly alarmed by the response.
"I gave him opportunities to show me something, I thought he was defenseless," Russell said of Alvarado. "I didn't want to see him get hurt. When you don't have a defense I don't think any fan or referee wants a fighter to get permanently hurt."
Rios said afterward he's open to either a rematch with Alvarado or the possibility of fighting the winner of the Dec. 8 Manny Pacquiao-Juan Manuel Marquez fight.
Rios moved to junior-welterweight after twice failing to make 135 pounds, first losing his world lightweight belt in New York in December and then missing a chance to regain the belt in April in Las Vegas.
"He tested my chin, I had one, and now I'm ready for the next guy," Rios said.
Donaire (30-1, 19 KOs) was pressed back to the ropes in the ninth, took some punches and then responded with a straight right that dropped Nishioka and caused referee Raul Caiz Sr. to stop the fight at the 1:54 mark.
"We know we can end the fight with one punch," Donaire said. "When you do engage, Nonito is a surgeon. The demolition man comes in and knocks you out."
Donaire, who said he hurt his left hand early, and former WBC champion Nishioka (39-5-3) slumbered through the first five rounds, Donaire winning them with his hand speed and ability to move.