BEIJING, China (AP) -- Tyson Gay, Usain Bolt and Asafa Powell remained on course for an epic three-way battle in track's marquee Olympic event, all easily advancing on Friday into the semifinals of the 100 meters.

World record-holder Usain Bolt, center, had time to look over his shoulder during his heat victory.

Running in ideal conditions, Gay allayed fears that a lingering hamstring strain would affect his performance at the Beijing Games, coasting in both his heat and quarterfinal to go through.

The world champion injured his hamstring at the U.S. trials six weeks ago and had not run competitively since, raising doubts about his fitness.

He finished second behind Richard Thompson of Trinidad and Tobago in his quarterfinal in 10.09 seconds, easing up well before the finishing line.

"I felt good and relaxed. I just wanted to make it through," Gay said.

No one was as awesome as Bolt, though. At the halfway mark the world record-holder from Jamaica eased up, looked left and right -- not once, but twice -- and with 9.92 still ran the fastest time ever in China.

"I just ran the first 50 meters. Then I looked around to make sure I was safe and I shut it off," Bolt said.

Powell, who had been the world record-holder coming into the season, also moved through with consummate ease, clocking 10.02 in the last of the quarterfinals.

To show the potential of Saturday's final, the three together own the eight fastest times in history.

Late in the Beijing evening, Ethiopian Tirunesh Dibaba produced a stunning last lap burst to win the women's 10,000 meters in a time of 29 minutes 54.68 seconds -- an Olympic record and the second fastest in history.

Off a strong pace from the start, it boiled down to a battle for gold between Dibaba and Ethiopian-born Elvan Abeylegesse of Turkey.

Dibaba clocked 60.29 seconds for the last 400m to clinch her first Olympic gold with Shalane Flanagan setting a United States record in claiming bronze.

The first track and field medal went to Poland's Tomasz Majewski, who won the won the men's shot putt gold ahead of Christian Cantwell of the United States and third-placed Andrei Mikhnevich of Belarus.

Kenyan-born American Bernard Lagat successfully set off on his quest for a 1,500m-5,000m double, easily reaching the semifinals by finishing fourth in his opening heat of the 1500.

In the easiest leg of the double, he will face a slew of Kenyans and 2005 world champion Rashid Ramzi of Bahrain, who had the fastest qualifying time.

Hyleas Fountain of the United States ran the fastest 200 meters to finish the night Friday with a lead in the heptathlon in the absence of Carolina Kluft, the dominant Swede.

The 27-year-old American had 4,060 points from the first four of seven disciplines, a 64-point lead over Ukraine's 2004 world indoor champion Nataliya Dobrynska, who hit the lead in the shot put -- her strongest event.

Kelly Sotherton of Britain, who took a bronze at the Athens Games and at the last world championships, was in third place with 3,938 points with three disciplines remaining on Saturday's schedule.

Russia's Anna Bogdanova was fourth with 3,922 points, 10 ahead of Lyudmila Blonska, the 2006 world indoors champion and silver medalist at the world championships last year.

Fountain, who was ahead after the 100-meter hurdles and high jump but dropped back to second after the shot put, ran 23.21 to lead the 39-woman field in the 200s.

In the individual 800m, Kenyans Pamela Jelimo and Janeth Jepkosgei breezed through into Saturday's semifinals, easily winning their heats. The showdown between the two in Monday's final is one of the most anticipated races of the games.

As usual, Jepkosgei was a front-runner from the starting gun to dominate her heat. "This is what I needed. I needed to know about my body," the world champion said.

Jelimo, who had dominated the season coming into Beijing, bided her time until the final lap before kicking to go through.

"I've done what I need to do. It's important just to be there at this moment," Jelimo said. "I'm through to the semifinals, that's the main thing."

Sydney 2000 Olympic champion Maria Mutola is in her final major competition before retiring at the end of the year, but still had the fastest qualifying time of 1:58.91.

BEIJING, China (AP) -- Tyson Gay, Usain Bolt and Asafa Powell remained on course for an epic three-way battle in track's marquee Olympic event, all easily advancing on Friday into the semifinals of the 100 meters.

World record-holder Usain Bolt, center, had time to look over his shoulder during his heat victory.

Running in ideal conditions, Gay allayed fears that a lingering hamstring strain would affect his performance at the Beijing Games, coasting in both his heat and quarterfinal to go through.

The world champion injured his hamstring at the U.S. trials six weeks ago and had not run competitively since, raising doubts about his fitness.

He finished second behind Richard Thompson of Trinidad and Tobago in his quarterfinal in 10.09 seconds, easing up well before the finishing line.

"I felt good and relaxed. I just wanted to make it through," Gay said.

No one was as awesome as Bolt, though. At the halfway mark the world record-holder from Jamaica eased up, looked left and right -- not once, but twice -- and with 9.92 still ran the fastest time ever in China.

"I just ran the first 50 meters. Then I looked around to make sure I was safe and I shut it off," Bolt said.

Powell, who had been the world record-holder coming into the season, also moved through with consummate ease, clocking 10.02 in the last of the quarterfinals.

To show the potential of Saturday's final, the three together own the eight fastest times in history.

Late in the Beijing evening, Ethiopian Tirunesh Dibaba produced a stunning last lap burst to win the women's 10,000 meters in a time of 29 minutes 54.68 seconds -- an Olympic record and the second fastest in history.

Off a strong pace from the start, it boiled down to a battle for gold between Dibaba and Ethiopian-born Elvan Abeylegesse of Turkey.

Dibaba clocked 60.29 seconds for the last 400m to clinch her first Olympic gold with Shalane Flanagan setting a United States record in claiming bronze.

The first track and field medal went to Poland's Tomasz Majewski, who won the won the men's shot putt gold ahead of Christian Cantwell of the United States and third-placed Andrei Mikhnevich of Belarus.

Kenyan-born American Bernard Lagat successfully set off on his quest for a 1,500m-5,000m double, easily reaching the semifinals by finishing fourth in his opening heat of the 1500.

In the easiest leg of the double, he will face a slew of Kenyans and 2005 world champion Rashid Ramzi of Bahrain, who had the fastest qualifying time.

Hyleas Fountain of the United States ran the fastest 200 meters to finish the night Friday with a lead in the heptathlon in the absence of Carolina Kluft, the dominant Swede.

The 27-year-old American had 4,060 points from the first four of seven disciplines, a 64-point lead over Ukraine's 2004 world indoor champion Nataliya Dobrynska, who hit the lead in the shot put -- her strongest event.

Kelly Sotherton of Britain, who took a bronze at the Athens Games and at the last world championships, was in third place with 3,938 points with three disciplines remaining on Saturday's schedule.

Russia's Anna Bogdanova was fourth with 3,922 points, 10 ahead of Lyudmila Blonska, the 2006 world indoors champion and silver medalist at the world championships last year.

Fountain, who was ahead after the 100-meter hurdles and high jump but dropped back to second after the shot put, ran 23.21 to lead the 39-woman field in the 200s.

In the individual 800m, Kenyans Pamela Jelimo and Janeth Jepkosgei breezed through into Saturday's semifinals, easily winning their heats. The showdown between the two in Monday's final is one of the most anticipated races of the games.

As usual, Jepkosgei was a front-runner from the starting gun to dominate her heat. "This is what I needed. I needed to know about my body," the world champion said.

Jelimo, who had dominated the season coming into Beijing, bided her time until the final lap before kicking to go through.

"I've done what I need to do. It's important just to be there at this moment," Jelimo said. "I'm through to the semifinals, that's the main thing."

Sydney 2000 Olympic champion Maria Mutola is in her final major competition before retiring at the end of the year, but still had the fastest qualifying time of 1:58.91.