ANAHEIM, Calif. -- After just 90 seconds of his last title defense -- May 27 in Los Angeles against mixed martial arts legend Royce Gracie -- Matt Hughes was celebrating a victory and making plans for a vacation.

After 90 seconds Saturday at the Arrowhead Pond, Hughes was bleeding from the mouth and nose and in jeopardy of surrendering his UFC welterweight title again.

But even after he lost the first round badly, Hughes wasn't concerned. He was so confident, in fact, he looked over at UFC owner Lorenzo Fertitta and winked.

"He looked at me and said, 'I've got him,' " Fertitta said. "I thought he lost the first two rounds, but I kind of thought, 'Well, OK. If you think you did, that's all that matters.' "

Penn nearly scored a submission in the second round, but Hughes survived, then dominated the third. He knocked Penn down and pounded him until referee John McCarthy dived in to stop it at 3:43 of the third.

"I was close" to submitting in the second, Hughes conceded. "Honestly, you know what I did? I said a little prayer."

Penn wasn't the same fighter in the third round, though, that he was in the first two. He had shocked Hughes in a 2004 fight at Mandalay Bay, moving up from lightweight and scoring a submission over Hughes to lift the title from him.

It looked like more of the same Saturday for the first 10 minutes. Penn had things his way and Hughes only could bank on his superior conditioning.

Penn has fluctuated in weight greatly over the years and has been criticized for a lackadaisical approach to training. He weighed 166 1/2 to Hughes' 170 Saturday, but Hughes proved to be correct.

"I'll tell you what: If he had the gas tank to go five rounds, he could have won every round," Hughes said after improving to 42-4 and winning for the 20th time in the last 21 fights. "But I knew his cardio was going to be his weak spot, so when I came back from the first round, even though I knew I lost it badly, I smiled."

But the display of confidence didn't change things much in the second. Penn took the fight to the mat in the first minute of the second and worked much of the round on an armbar and a triangle choke.

The immensely powerful Hughes managed to pull Penn's arm from around his neck briefly to allow him to grab a few gulps of air.

But things changed drastically in the third. Hughes came out jabbing and Penn seemed lethargic even before Hughes connected well.

Hughes said he knew he could improve his attack.

"I didn't set my shots up right and I should have known," Hughes said. "My boxing's good enough to where he wasn't going to hurt me. I felt real comfortable on my feet. Instinct-wise, I thought there was a shot there and so I took it."

Hughes knocked Penn down with a combination that was the beginning of the end. Hughes trapped Penn's left arm with his legs, denying Penn the use of it for defensive purposes.

He then began to pound on Penn's unguarded head and landed at least 15 thudding shots before McCarthy stopped it.

Penn was barely able to walk and his handlers literally were dragging him from the ring to his locker room.

After the bout, Georges St. Pierre, who was supposed to fight Hughes on Saturday until he had to pull out with an injury, grabbed the in-ring microphone from Joe Rogan, who was interviewing Hughes.

"I was not impressed," St. Pierre said as the crowd booed.