PHILADELPHIA — Any thoughts of a Tyson Gay vs. Asafa Powell showdown at the Penn Relays in a sort of Beijing Olympics preview were scuttled when the Jamaican withdrew.

Any thoughts of Gay anchoring the United States to a 9-0 record in "USA vs. the World" 400-meter men's relay went by the wayside Saturday when a teammate was poked in the eye, of all things.

Gay's squad — the same quartet that won the 2007 world championship — wound up only fourth in a race won by Jamaica.

"By the time I got the stick," said Gay, world champion at 100 and 200 meters, "it seemed like Jamaica had already crossed the finish line."

Jamaica's Marvin Anderson, Michael Frater, Nesta Carter and Dwight Thomas finished in 39.04 seconds. Powell, the world-record holder in the 100, withdrew Friday, citing a chest muscle injury.

"This is a huge confidence boost for us. We didn't have Asafa Powell out here with us," Frater said. "So we especially wanted to show that even though we may not have arguably the best sprinter in the world, we could still go there and compete against a very good U.S. team."

The leadoff man for Gay's squad, Leroy Dixon, was scratched in the left pupil by the finger of the Canadian runner in the next lane. Dixon paused, startled, then started racing again and handed off to Wallace Spearmon. But there was too much of a gap to recover.

Afterward, Dixon's vision was blurry and he couldn't keep his eye open. He was wearing a large Band-Aid patch over his injured eye.

"That was a new one," Spearmon said. "I thought we were racing Mike Tyson."

That race was part of an uneven showing by the Americans, who took three of the six "USA vs. the World" events on an overcast day with swirling wind. Team USA lost as many races as it had over the previous four Penn Relays combined, when it went 21-3.

Cheered on by thousands of countrymen waving green-black-and-yellow flags and blowing horns in the Franklin Field crowd of 49,831, Jamaica also won the women's sprint medley. In the nine years of "USA vs. the World," the only other time Jamaica is listed as having won two events is 2001, when its 1,600 women's team crossed the finish line second to a Marion Jones-led U.S. team that was later stripped of its first-place finish.

In the men's 1,600, reigning Olympic and world 400 champion Jeremy Wariner ran an anchor leg of 43.88 seconds to give the United States the victory. Another U.S. team finished second.

Afterward, Wariner repeated his intention to break Michael Johnson's world record in the 400, saying, "I'm going to go into each race with that on my mind."

Johnson is Wariner's agent.

"Michael told me it could be broken at any meet, any time this season, as long as you work hard for it. So it could be in Oslo, it could be at the Olympics or it could be at the Grand Prix final past the Olympics. Or it could be in three years," Wariner said. "As long as I go out there and race for it, it will come."

Another American expected to be one of the stars in Beijing, Allyson Felix, helped the United States win the women's 400 and 1,600 relays, pulling away from countrywoman Sanya Richards down the stretch in a thrilling finish to the shorter race.

"It's really encouraging to get out there and be able to hang with everybody else, knowing that there's so much work to do," Felix said.

Consider that a bit of modesty from the 2004 Olympic silver medalist at 200 meters. In addition to overwhelming Richards in the 400 — "Allyson brought it home very strongly," teammate Lisa Barber said — Felix ran her lap of the 1,600 in 50.1 seconds, the race's fastest leg.

That allowed the United States to win the 1,600 in a Penn Relays-record 3:22.16.

Like Gay, Felix said she would love to compete in four events at the Aug. 8-25 Summer Games: the 100 and 200 meters, and both relays.

Gay isn't bothered by the idea of not facing Powell head-to-head before Beijing.

"When it's time for us to race, we're going to race. At the same time, I think it is good for the sport if we don't race until the big meets," Gay said. "It's good because it keeps everyone on their toes."