Tyson Gay coasted through two 100 meter preliminary heats, showing his left hamstring is just fine six weeks after hurting it at the U.S. Olympic trials.

World record-holder Usain Bolt and the guy he took it from, fellow Jamaican Asafa Powell, also advanced easily to the final 16. All three are expected to make Saturday's final -- perhaps the most highly anticipated event of the 10-day track and field meet at the Bird's Nest.

In the semis, Powell and Gay will run the same heat, while Bolt's biggest challenge in the other semi figures to be from America's Walter Dix and Derrick Atkins of the Bahamas.

"I feel pretty good. It felt pretty relaxed," Gay said after his second race. "I just wanted to make it through."

Tirunesh Dibaba of Ethiopia won the 10,000 meters in an Olympic record 29 minutes, 54.66 seconds. Turkey's Elvan Abeylegesse took silver, while Shalane Flanagan set an American record at 30:22.22 to win bronze. It was the first U.S. medal in the 10K since 1992.

In the men's 1,500, Bernard Lagat, Leo Manzano and U.S. team flagbearer Lopez Lomong all made it out of their first races.

The men's shot put was a big disappointment for the Americans. Instead of sweeping, they got only a silver from Christian Cantwell. Poland's Tomasz Majewski won gold.

Reese Hoffa, the reigning world champion, was seventh and his U.S. teammate Adam Nelson, the two-time Olympic silver medalist, threw with hurt ribs and didn't make it into the final eight.

"We expected more from ourselves," Nelson said.

Softball

Turns out, the U.S. women are as dominant as ever.

First they set an Olympic record with four homers in a 7-0 victory over Japan. Then they resumed a rain-stopped game against Canada, trailing 1-0. After being five outs from losing, they wound up winning by the lopsided score of 8-1.

The Americans broke the game open with four runs in the sixth, helped by two errors by Canadian shortstop Jennifer Salling, and a wild pitch and hit batter by Dione Meier of Canada, which beat China 1-0 earlier in the day.

In other games, Australia beat Taiwan 3-1 and Venezuela beat the Netherlands 8-0.

Women's basketball

The U.S. women started slowly, then got clicking, pounding Spain 93-55. Tina Thompson scored nine of her 17 points during a game-breaking 20-5 run in the third quarter and Lisa Leslie added 14 points and 11 rebounds.

With the win, the U.S. has 29 straight victories in Olympic contests. The last loss was to the Unified team in the 1992 semifinals.

In other games Friday, Australia topped Latvia 96-73, Russia edged Brazil 74-64, the Czech Republic beat New Zealand 90-59, China routed Mali 69-48 and Belarus topped South Korea 63-53.

Tennis

An American won't win the men's singles title.

James Blake, the last hope left, lost to Chile's Fernando Gonzalez, who blew four match points before winning 6-4, 5-7, 11-9.

Blake then accused Gonzalez of failing to concede a point with Gonzalez serving at 8-9 in the final set. On the first point, Blake hit a backhand passing shot long but contended the ball hit Gonzalez's racket before landing, as TV replays confirmed.

"Playing in the Olympics, in what's supposed to be considered a gentleman's sport, that's a time to call it on yourself," Blake said. "Fernando looked me square in the eye and didn't call it."

Gonzalez said he was uncertain whether the ball hit his racket.

New women's No. 1 Jelena Jankovic lost in the quarterfinals to No. 6 Dinara Safina, who will play China's Li Na in the semifinals. The other semi will pit Russians Elena Dementieva and No. 9 Vera Zvonareva.

In doubles, Roger Federer kept alive his hope for an Olympic gold medal, joining Swiss teammate Stanislas Wawrinka to upset top-ranked American twins Bob and Mike Bryan and win a spot in the final.

Federer and Wawrinka will face unseeded Simon Aspelin and Thomas Johansson Saturday. The Swedes beat French duo Arnaud Clement and Michael Llodra 7-6 (6), 4-6, 19-17.

Venus and Serena Williams, both eliminated in singles Thursday, won twice to reach the semifinals in doubles, but Americans Lindsay Davenport and Liezel Huber were eliminated in the quarterfinals by Anabel Medina Garrigues and Virginia Ruano Pascual, of Spain.

Baseball

The U.S. baseball team is in trouble. They fell to 1-2, lost a key player to an injury and have angered the mighty Cubans by accusing them of dirty play after losing to them 5-4 in 11 innings.

In their first game under a wacky extra-inning format -- from the 11th on, teams automatically get runners on first and second and can start anywhere in the batting order -- the Americans gave up two runs in the top of the inning, then fell one shy in the bottom. The last at-bat started with Jayson Nix squaring to bunt and fouling the pitch off his left eye.

Nix later underwent microsurgery to close about a 2-inch wound above his eye and will not play again in China.

The other early game was the first to invoke the new extra-inning rule. China won it 8-7 over Taiwan in 12 innings. Also, South Korea beat Canada 1-0 and Japan beat the Netherlands 6-0.

Women's volleyball

With China's president watching, the U.S. team coached by former Chinese star Jenny Lang Ping knocked off the hosts in five sets. The Americans are 3-2 overall, in good shape to advance. China fell to 2-2.

In other games, Brazil, the top-ranked team in the world, defeated Kazakhstan 3-0. The Brazilians are undefeated after four pool matches and are assured a spot in the quarterfinals.

Poland won its first match of pool play with a 3-0 victory over winless Venezuela, Russia defeated Algeria in three sets, Italy defeated Serbia 3-0 and Cuba defeated Japan 3-0.

Women's soccer

Natasha Kai scored on a header in extra time, sending the defending champion Americans into the semifinals with a 2-1 victory over Canada. The game was suspended for one hour and 40 minutes during the first half because of lightning.

Brazil advanced with a 2-1 win over Norway, Japan beat China 2-0 and Germany won against Sweden 2-0.

Japan will play the United States in the semifinals, while Brazil will take on Germany.

Weightlifting

China got its seventh and eighth gold medals in weightlifting, with Lu Yong winning the fourth by a man and Cao Lei taking the fourth for a woman.

"We have proved our strength," Cao said.

Kendrick Farris set two U.S. records in the men's 85-kilogram division, but had to settle for eighth place.

Cycling

It was a big day for Britain, with the British beating France for the gold in men's team sprint and Bradley Wiggins setting an Olympic record in qualifying for the 4,000-meter individual pursuit.

American Taylor Phinney -- the 18-year-old son of 1984 gold medalist Connie Carpenter-Phinney and '84 bronze medalist Davis Phinney -- advanced in the pursuit race with his parents watching from the front row.

"It is just another race and I like to think of it that way," Taylor Phinney said. "But it's also way bigger than I thought it would be."

Badminton

Du Jing and Yu Yang won China's first-ever gold in badminton, taking women's doubles over a South Korean team. Another Chinese tandem got the bronze, beating a Japanese duo that knocked off the top-seeded, defending Olympic champions.

Diving

China's Phelp-ian run to eight gold medals still looks good, with Guo Jingjing leading after the women's 3-meter springboard preliminaries.

Guo, who already successfully defended her synchronized springboard title with partner Wu Minxia, is in position to claim her second consecutive Olympic 3-meter individual title.