LAS VEGAS—Speed, indeed, kills.

David Diaz acknowledged this on Saturday after he was knocked out by the speedy, rapid-punching Manny Pacquiao and yielded his World Boxing Council lightweight crown to the Filipino ring icon.

“It was all speed,” said Diaz, during the post-fight interview. “He boxed more than I thought he would box. No excuses.”

After regaining his bearings on the ring, the 32-year-old Diaz admitted he never saw the killer punch—prefaced by a head-snapping jab—coming.

“I think it was the left hand,” Diaz said. “He was f****ng fast. I didn’t see [the left hand] coming.”

The ever-gracious Diaz was down on the floor for more than a minute and had to be seated on a stool after Pacquiao caught him with a left hook in the ninth round.

“He’s a clean fighter.”

And, as Diaz himself admitted, a really good one.

“I was taking his punches and I said ‘hey, he doesn’t hit that hard’ and all of a sudden I’m on the floor and [wondering] ‘what the heck happened?’”

Perhaps Diaz didn’t even know that a worried Pacquiao tugged on his arms to help him up after referee Vic Drakulich declared the fight over with 2:24 gone in the round.

Pacquiao’s performance validated trainer Freddie Roach’s faith in the Filipino ring icon. Roach said in pre-fight interviews that he was certain Pacquiao would knock Diaz out.

“I knew that it (fight) would last long because Diaz is so durable,” said Roach, a multi-awarded trainer. “But sooner or later, I knew Manny’s punches would break him down.”

Diaz, however, said the devastating loss won’t make him a quitter.

“I had great fun,” said Diaz, who had a mouse on his left eye and cuts on the right eyebrow and the bridge of his nose.

In a show of class, instead of proceeding directly to the Valley Hospital where he will be stitched up, Diaz opted to appear before the media.

The 32-year-old Diaz even thanked the Filipinos for their fair treatment of him during the fight’s promotional tours in the United States.

“The only thing about Manny is he hit me a little more than I hit him,” joked Diaz, who was accompanied by wife Tanya and close friends.