Aug. 13, 2008, 12:10 p.m. (ET)

BEIJING (AP) The South Koreans were secretive and sure of themselves leading up to their Olympic baseball opener against the United States. They made all the big plays when it mattered most and took advantage of each American mistake, too.

Lee Jong-wook hit a go-ahead sacrifice fly with one out and South Korea answered the Americans' ninth-inning rally with one of its own, beating the U.S. 8-7 on Wednesday night.

"It was a marvelous game, an amazing game," South Korean manager Kim Kyung-moon said. "But a tough game."

Lee Taek-keun's slide home easily beat the throw for the winning run, and he celebrated on his knees for a long while before joining his jubilant teammates. The South Koreans then tipped their caps to supporters who were on their feet in the bleachers all night.

The Americans had seemed poised for a comeback victory after Matt Brown hit a go-ahead two-run single with two outs in the top of the ninth, but South Korea rallied against closer Jeff Stevens in the bottom half.

The stunned U.S. players did not stop for post-game interviews, despite nearly two dozen reporters calling for them. The Americans had a quick turnaround to face the Netherlands on Thursday morning.

"It was a heck of a ballgame," U.S. manager Davey Johnson said. "My ballclub battled back, came back from behind, got some clutch base hits and were in position to close it out in the ninth and gave up a tough hit."

In earlier games Wednesday, Canada beat China 10-0 in eight innings to spoil the Chinese team's Olympic debut and Taiwan defeated the Netherlands 5-0.

Pinch-hitter Jeong Keun-woo doubled to start the bottom of the ninth for South Korea, which battered U.S. starter Brandon Knight and pulled off the biggest upset on the first day of the eight-team, round-robin tournament.

South Korea tied it when second baseman Jayson Nix's throw home on Lee's grounder was wide and allowed Jeong to score.

"The manager said to me to be ready to go out as a pinch-hitter," Jeong said.

Mike Hessman homered leading off the ninth against Han Ki-joo, who then allowed a single to Taylor Teagarden and Brian Barden's double for his third hit of the game.

Kim then turned to Yoon Suk-min and the Americans lifted Teagarden at third for speedy pinch-runner Dexter Fowler. Yoon struck out John Gall and got Nix to pop up before Terry Tiffee's walk loaded the bases for Brown - and his sharp single found the gap in left-center.

"Going to bat in that last inning, we've got a good lineup from top to bottom," Barden said. "I've seen us hit for a week and a half, two weeks, and there was no doubt we were going to go out there and put some solid at-bats together and put a push toward coming back, and we did. It's just a sign of how good of a team we are. It's just too bad we had a couple miscues at the end, but I feel like we played a pretty strong game."

Nate Schierholtz also had a solo homer for the U.S. team after hitting four during six exhibition games. The Americans are a medal hopeful after missing out on a bid to the 2004 Athens Games. The U.S. team won gold in Sydney in 2000.

About a dozen pro scouts turned out before heading next door to see to Japanese pitching prospect Yu Darvish against Cuba.

Lee Dae-ho - South Korea's burly and imposing designated hitter - hit a two-run homer and nearly connected again in the fifth with a drive that center fielder Schierholtz caught at the wall. He then hit one just outside the right-field foul pole in the eighth.

The U.S. team, which led 1-0 after the first following Brown's RBI single, left a base runner on third in the eighth.

Neither manager would announce his starter leading up to the game.

When Johnson and Kim met at home plate minutes before first pitch, they didn't make eye contact until the very last moment for a polite handshake and tip of the cap.

Johnson went with an experienced lineup and started Knight, the oldest player on the American roster at 32. The right-hander was tagged for six runs on eight hits in 4 1-3 innings. He struck out two and walked two.

It was Knight who last month made an emergency start for the New York Mets while Pedro Martinez was gone for his father's funeral in the Dominican Republic.

New York then designated Knight for assignment the next day, allowing him to stay on the Olympic team because he was off the Mets' roster.

South Korea's fans were out in force and overmatched the U.S. fans - waving flags, cheering loudly and banging noisemakers.