Aug. 15, 2008, 10:44 a.m. (ET)

BEIJING (AP) Michel Enriquez lined a go-ahead two-run single to right in the 11th inning and defending champion Cuba stayed unbeaten in the Olympic baseball tournament, riding burly reliever Pedro Lazo to a 5-4 victory over the United States on Friday.

Baseball's new extra-innings rule for international play got used for the first time Friday - not once, but twice. Beginning in the 11th inning, runners go to first and second and teams can start at any point in their batting order.

In the other early game, China earned its first ever Olympic victory with a hard-fought 8-7 win over Taiwan in 12 innings.

Jayson Nix fouled a ball off his left eye to start the bottom of the 11th and left the game, then Brian Barden laid down a perfect bunt to move runners to second and third for Terry Tiffee. He hit a sacrifice fly, but Matt Brown popped up to the catcher to end it for the Americans.

Nix left the game for the hospital and is likely finished for the rest of the Beijing Games.

"He's in bad shape," said U.S. manager Davey Johnson.

Cuba is 3-0 and in strong position for a medal. At 1-2, the U.S. cannot afford many more slipups if it wants to reach the medal stand.

U.S. first baseman Terry Tiffee isn't a fan of the new rule.

"The whole extra-innings thing I think is bogus," Tiffee said.

But Cuba manager Antonio Pacheco said: "It's a rule for all the world."

In night games, South Korea edged Canada 1-0 in a game that saw Ryu Hyun-jin throw a complete-game shutout. He gave up five hits and three walks and struck out six.

South Korea's only run came on a solo homer in the third-inning by Jeong Keun-woo. Mike Johnson threw six strong innings for Canada but took the loss.

Canada dropped to 1-2 and will play the U.S. on Saturday, while South Korea improved to 2-0.

Japan beat the Netherlands 6-0 in the other evening game. Toshiya Sugiuchi pitched seven scoreless innings, and Takahiro Arai went 2-for-4 with 2 RBIs for Japan, which improved to 2-1 while the Dutch fell to 0-3.