Cain Velasquez takes UFC title from Brock Lesnar

The first heavyweight champion of Mexican descent emerged Saturday night, as Cain Velasquez, the son of migrant lettuce farmers, defeated Brock Lesnar to capture the Ultimate Fighting Championship title fight.

Velasquez, 28, survived an immediate charge by the heavier Lesnar by blasting punches that knocked the nearly 300-pound former pro wrestling star stumbling across the octagon and crashing to the canvas twice before a final Velasquez flurry caused referee Herb Dean to stop the fight 4:12 into the first round at Anaheim’s Honda Center.

An emotional Velasquez raised his arms in the center of the canvas, then covered his face in jubilation as a capacity crowd roared.

“I didn’t want to hold anything back,” Velasquez (9-0) said afterward. “We worked on all these scenarios.”

Lesnar (5-2) was left to sit on a stool, as a ringside doctor patched up a nasty cut under his left eye.

Velasquez was almost a 2-to-1 underdog and fought for a guaranteed purse one-fourth that of Lesnar, who had twice successfully defended his belt and took at least a 20-pound weight advantage over the product of Yuma, Ariz., who now lives and trains in San Jose.

Lesnar clearly wanted to rely on his girth in this fight, barreling after Velasquez, who responded by delivering knees to the champion’s head. Lesnar again pressed Velasquez to the cage and the pair then stood toe to toe with 3:11 left in the round.

Velasquez threw a combination of punches and was atop Lesnar, throwing rights to the head and even a backhanded right to Lesnar’s left ear. Lesnar struggled to rise, but Velasquez landed another combination anchored by a flush right that sent Lesnar staggering and falling across the octagon.

For the second consecutive fight, Lesnar experienced major first-round trouble. In July, he withstood the onslaught of Shane Carwin, who fatigued and lost quickly in the second round by submission.

Velasquez is a cardiovascular beast, in the peak of fitness, and his unyielding effort made Lesnar’s conditioning a matter for future scrutiny.

The challenger kept punching, landing a hard right that sent Lesnar back down, covering his head in vain. Velasquez hammered Lesnar with consecutive left hands to the head, and referee Dean waved the fight off.

The new champion pounded his strong heart, hopped on the canvas in celebration and strapped on his new belt.

Lesnar said he would pursue a rematch. “That’s what a champion does, right?” he said.

Also Saturday, former Strikeforce champion Jake Shields earned a UFC welterweight title shot in a controversial split-decision victory over Martin Kampmann in Shields’ UFC debut.

Shields (26-4-1) claimed judges’ scores of 30-27 and 29-28, and Kampmann (17-4), who appeared to outwork Shields, won a 29-28 score.

Huntington Beach’s former UFC light-heavyweight champion Tito Ortiz’s lost a unanimous decision to Matt Hamill. The defeat kept former light-heavyweight champion Ortiz (16-8-1) winless in five fights since 2006, certainly extinguishing the hope he had expressed last week about returning to division title contention. Hamill improved to 11-2.

The card also featured a sensational welterweight victory by title contender Diego Sanchez (24-4) over Paulo Thiago (13-3) by a unanimous decision.

lance.pugmire@latimes.com

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