But it took only 30 seconds for Dos Santos to beat up Shane Carwin.
Just not the first 30 seconds of the fight, though.
No, this was not one of those first-minute knockouts that dot the résumés of both heavy-hitting heavyweights. In fact, not a single punch was thrown for nearly a minute of this No. 1 contender's bout, and when the first leather did connect, it was just a succession of short uppercuts that Dos Santos used not so much to hurt Carwin as to fend off the former NCAA Division II national champion wrestler's takedown attempt. The Brazilian succeeded in getting away, and for more than three minutes he stayed away, his quick, sharp jab keeping Carwin where his vaunted power could do no damage.
Then Dos Santos inflicted some damage of his own. He sent the former interim champion to the canvas with a crisp left-right combination with 45 seconds left in the first round, and pounced. Thirty seconds later, Carwin was back on his feet, but his face was a crimson mess after he'd taken 13 right hands to the head, rolled over, almost got choked out, then absorbed an unremitting barrage of 29 lefts. Dos Santos kept looking over at referee Herb Dean to see if he was going to jump in, and finally backed away to take a breather in the final seconds.
Carwin survived the horn, but he was as good as finished. From that point on, Dos Santos beat him to the punch and eluded most every offensive by "The Engineer" (12-2) on the way to a lopsided unanimous-decision victory that earned him a date with the champion, Cain Velasquez, likely October 8 in Houston at UFC 136.
"That's awesome," Dos Santos (13-1, 7-0 in the UFC) said afterward. "Thanks, God, for that. Much respect for Cain Velasquez, but Cain, I'm coming for you."
Velasquez, standing inside the cage a few feet away, smiled before walking over to congratulate his next challenger.
"He showed awesome standup, just like he does in all of his fights," said the champ, who hasn't fought since tearing a rotator cuff during last October's victory over then-titlist Brock Lesnar. Of Dos Santos he added, "He's always improving. He's the No. 1 contender. I'm excited to fight somebody like this."
Velasquez witnessed a performance as dominant, if not quite as explosive, as his belt-winning showing against Lesnar. Dos Santos made the 35-year-old look slow and confused. Again and again, Carwin put up an arm to block a punch only after it already had landed on his face. He didn't gas out, as he had in his unsuccessful bid for the belt worn by Lesnar last July, but he had little opportunity to throw more than one punch at a time.
Dos Santos is going to be a handful for anyone he steps in with, even the undefeated champ.
He wasn't the only fighter on the card who set himself up for a title shot. The skin and bones formerly known as Kenny Florian made his featherweight debut and, in a tight bout that turned his way as time wore on, won a unanimous decision over Diego Nunes to stake his claim as a top contender for Jose Aldo's title.
"I want to make a run for that belt," said Florian (15-5). "I beat one of the top guys in the world. Diego Nunes is going to be a future champion. He's as tough as they come, and I wanted to face someone like that and prove that I'm one of the best featherweights in the world."
He succeeded in doing so, but it wasn't easy. Nunes (16-2), faced with a seven-inch reach disadvantage, took a while to find his range. But eventually he started landing, even dropping Florian with a left-right in the final seconds of the first. But Florian, who was booed lustily by a crowd that saw him wear a Boston Bruins jersey to Friday's weigh-ins, remained relentless with his punches and kicks in the clinch, and in the second and third rounds he appeared to be the fresher fighter.
That was a bit of a surprise, considering that this was the first time the longtime lightweight, who's also fought in the UFC at welterweight and even middleweight, had to make the cut to 145 pounds. He looked gaunt. But he never drooped.
"I'll be honest with you, Joe, that was the hardest thing I've ever done in my life," Florian told Joe Rogan in the cage afterward. He started his cut "above 180 pounds" after undergoing knee surgery. "On the couch for two months," said Florian, "doing nothing."
He sure had something to do Saturday night, and like Junior Dos Santos, he got the job done. Perhaps that was enough to get Florian what Dos Santos earned with his win: a shot at a few extra pounds of leather and the brass and glory that goes with it.