BEIJING • The thank-you card soon will be in the mail.

Maybe LaShawn Merritt could send it from the Chinese capital. Nah, he’ll probably wait until he gets home.

Noticing a subtlety in Jamaican Usain Bolt’s lastrecord-setting run, Merritt extended his strides down the homestretch of the 400 meters Thursday to upset defending Olympic champion Jeremy Wariner in a U.S. sweep at the Beijing Games.

Merritt, 22, of Suffolk, Va., won his first Olympic gold medal in a personal-best 43.75 seconds, the fastest time in the world this year. Wariner, 24, of Waco, Texas, finished in 44.74 for silver, and David Neville, 24, of Valencia, Calif., crossed in 44.80 with a dive for bronze.

Bolt took long, graceful strides Wednesday in winning the 200 with a world-record time of 19.30, 0.02 of a second faster than the mark American Michael Johnson set at the 1996 Atlanta Games.

After Merritt ran neck and neck with Wariner and Neville into the turn, he mimicked Bolt, turning powerful but compact steps into what looked like enormous, effortless leaps.

“I actually focused on running on that backstretch,” said Merritt, who dedicated his win to his late brother. “I ran the backstretch like I wanted a gold. I wanted to go out and run like I wanted to win.

“I know Jeremy is going to bring his ‘A’ game, and everybody in the field is going to bring their ‘A’ game. I had to bring my ‘A-plus’ game. … I was just the better man.”

Wariner maintains his motor never started working after the turn.

“I came off the turn, and I felt good,” he said. “When I tried to move, it wasn’t there. If I would have had the race I had in the semifinals, it would have been a closer race.”

The victory gives Merritt, a habitual runner-up in big events, enough prestige to escape the shadow of Wariner, who has two world championships in the 400, including last year’s crown at Merritt’s expense.

“He didn’t run the race that he wanted to run, and that was on him,” Merritt said. “All I wanted to do was cross the finish line first. If it was by a large margin or by a little bit, I wanted to cross first. And that’s what I did.”-CONTACT THE WRITER: 636-0256 or brian.gomez@gazettedev.gazette.com. Check out our Olympics blog at gazetteolympics.freedomblogging.com

Photo by MARK REIS, THE GAZETTE