Conor McGregor stuns Jose Aldo in 13 seconds to take UFC featherweight title

McGregor (19-2) finished the fight with an electrifying exchange shortly after the opening bell, slipping Aldo's lead right and cracking Aldo on the jaw with a huge left hand.

Aldo (25-2) actually finished his punch and hit McGregor with a left, but the champ fell senseless to the ground andMcGregor pounced, only to be pulled off in victory.

Aldo had won 18 consecutive fights over the last 10 years, but nothing seems to slow McGregor. The loquacious Irish brawler goaded Aldo throughout the promotion of their delayed bout, only to back up every word he said.

In the night's other big fight, Luke Rockhold claimed the UFC middleweight title with a fourth-round stoppage of previously unbeaten champion Chris Weidman.

Rockhold (15-2) finished it with brute style, pounding Weidman on the ground late in the third and again in the fourth. When referee Herb Dean finally pulled Rockhold off the bloodied Weidman (13-1), the new champion collapsed face-down on the canvas in relief.

Rockhold has stopped his last five opponents. He seized control of the fight when Weidman attempted to throw a wheel kick in the third round. Rockhold dodged it and took the champ to the ground - the first time Weidman had ever been taken down in a UFC fight.

"He shouldn't be trying that kind of stuff on me," Rockhold said.

The bout matched the world's top two 185-pounders in the prime of their careers, and Rockhold backed up his incredible athleticism with a superb all-around performance.

The fighters didn't touch gloves to start, and they both landed solid blows in a competitive first round. Rockhold had control of Weidman in early stretches, and he gave a superior striking performance in the second round.

After the wheel kick went wrong, Rockhold rained blows on Weidman's head for the final minute of the third round, but Dean decided not to stop the fight. But Rockhold got back on top again in the fourth, and Weidman finally couldn't defend himself effectively.

Weidman had reigned atop the division since dethroning long-reigning champ Anderson Silva in 2013 and breaking Silva's leg in the rematch. Injuries limited Weidman's activity, but Rockhold established himself as the clear No1 contender with four straight UFC victories since a testosterone-aided Vitor Belfort stopped him in Rockhold's only loss in 14 fights since November 2007.

Weidman and Rockhold took a back seat to McGregor and Aldo during the event's promotion, but they also traded verbal jabs for several months after Rockhold called out the champion. Rockhold insisted Weidman had gaping holes in his game, while Weidman claimed Rockhold was unexceptional in any MMA discipline.

For more information go to The Guardian.com. Photograph: John Locher/AP