CARSON, California (AP) " Oscar Valdez defended his WBO featherweight title with a tenacious performance on Saturday night, knocking down Colombia's Miguel Marriaga in the 10th round of a unanimous-decision victory.
Jessie Magdaleno defended his WBO super bantamweight belt with a second-round stoppage of Brazil's Adeilson Dos Santos while Gilberto "Zurdo" Ramirez defended his WBO super middleweight title with a lopsided decision over Ukraine's Max Bursak in the famed outdoor ring at StubHub Center.
U.S. Olympic silver medalist Shakur Stevenson also won his professional debut on the card, beating Edgar Brito by technical unanimous decision after dominating five rounds.
Valdez (22-0) and Marriaga (25-2) put on a show appropriate for a venue that has become famous for hosting innumerable entertaining bouts over the years.
Valdez started quickly but had to work hard just to survive, let alone to remain unbeaten with his second defense of the title that he won in July.
"That was a learning experience, because now I know I can go the distance," said Valdez, who had never been stretched to 12 rounds. "That was one thing in the back of my mind. I've only done it in sparring."
Valdez staggered Marriaga with a series of hooks in the fourth round but Marriaga appeared to be turning the fight in his favor in the middle rounds with steady, aggressive work.
"I learned I've got to pace myself and not get too wild," Valdez said. "I was getting caught with some stupid shots. I said he would be a tough fight, and I think he showed in there that it wasn't easy."
In the 10th, Marriaga landed roughly 10 punches in a series before Valdez replied with a left hand that dropped Marriaga on his backside.
Marriaga eventually got up, but Valdez pounded him for the rest of the 10th. Both fighters rocked each other in a raucous 11th round, and the fighters traded combinations all the way to the final bell with the crowd on its feet.
The judges favored Valdez 119-108, 118-109 and 116-111. The Associated Press scored it 116-111 for Valdez.
Valdez was born in Nogales, Mexico, and raised in Tucson, Arizona, before fighting for Mexico in two Olympics. He had gone to a decision only twice since turning pro in 2012, but Marriaga tested Valdez to the limit.
"I expected a fight like this," Marriaga said. "I knew it would be a very tough fight. Oscar could have made it a little easier on himself the last couple of rounds, but he chose to fight those rounds."
Valdez, Ramirez and Magdaleno all trained in the same gym just a few miles away, and the so-called "Three Amigos" all defended their belts.
Ramirez (35-0) won his title with a one-sided thrashing of Germany's Arthur Abraham in April 2016 but his first title defense was delayed by surgery on his right hand. He would like to fight middleweight champion Gennady Golovkin soon but this dominant victory over Bursak (33-5-1) wasn't exactly a big drama show.
The rangy puncher from Mazatlan, Mexico, got off to a quick start against Bursak, but the fight slowed in the middle rounds. Both fighters got scoldings from referee Thomas Taylor for inside fighting and Bursak was docked two points for holding while the pro-Mexican crowd showed its disinterest by doing the wave.
Ramirez won 120-106 on all three scorecards.
Magdaleno (25-0, 18 KOs) won his title last November with an upset victory over Nonito Donaire, and his first title defense was remarkably smooth and swift.
The Las Vegas native knocked down Dos Santos twice in the second round, hurting him with a right hook to the temple and eventually finishing him with an overhand right.
"He kept trying to counter me, but I know I'm a faster and stronger guy than he is," Magdaleno said. "I waited for him to make a mistake, and that's when I countered with the right hook. Down he went."
Stevenson also put on a good show on the pay-per-view portion of the card in a winning debut for the touted featherweight from Newark, New Jersey.
Stevenson won every full round on every judge's scorecard, peppering Brito with the quick hands and agility that have made him one of the most hyped prospects in recent U.S. boxing history.