Gay was tipped to be Usain Bolt's main rival for 200m gold
World champion Tyson Gay is expected to be fit to run the 100m at the Olympics in Beijing.
The 25-year-old failed to qualify for the 200m, falling to the track early in his quarter-final at the US trials.
Gay appeared to grab his left hamstring, but the injury has been diagnosed as a light muscle strain, leading to a likely two-week lay-off.
He is due to return to action at the London Grand Prix on 25 July, where he is set to face Jamaican Asafa Powell.
"Tyson's only confirmed pre-Olympic competition is the 100 meters at the London Grand Prix and that is still on the schedule," his agent Mark Wetmore said.
Earlier, an American official had confirmed that Gay's injury was not severe enough to place his Olympic participation into jeopardy.
"The MRI showed a mild strain in the semitendinosus muscle," the official said in a statement.
"He is expected to engage in active rest for up to 12-14 days, with light physical activity increasing through that period, and then resume training."
Gay's likely return at the London meeting will pit two of the men who, along with Powell's Jamaican team-mate and world record holder Usain Bolt are expected to dominate the sprint events at the Olympics.
Gay, who won gold in the 100m and 200m in Japan last year, had been tipped to be Bolt's main rival in both sprint events, but the American policy of only picking the three fastest athletes in the trials means he misses out on the 200m squad.
Gay has already qualified for the 100m, recently running a wind-assisted 9.68 seconds to win the US trials.
That time was the fastest ever recorded over 100m, though the 4.1m/sec tailwind made the run illegal for the purposes of official records.
Gay also ran a legal time of 9.77 in the trials, the fourth fastest of all time and only bettered by Bolt and Powell.
In a statement, Gay said that the injury had worried him even before the heats.
"Before I went out on the track I felt a little tightness in my hamstring so I had kind of a bad feeling," he added.
"When I came off the first part of the curve the first two steps were fine, and then I felt it, sort of a pull, about 40 metres in.
"Once I was on the ground it didn't hurt as much as when it happened - I'll just get it worked on for a few days."
US athletics men's team coach Bubba Thornton said he was confident Gay will be ready to take his place alongside Powell and Bolt in what promises to be one of the highlights of the Olympics.
"I'm excited with the information I get," Thornton said. "I saw him earlier. He was smiling, getting on the elevator to get to that starting line - and he was walking.
"He's making preparations for the call in Beijing. I'm very confident he's going to be in place when they say, 'On your marks'."
And Thornton insisted that there were no plans to ask for an exception to the selection system to allow Gay to compete in the 200m.
"I believe in the system," Thornton said. "There will not be a person in this gathering that says, 'They politicised on me."
There was also disappointment for Allen Johnson at the trials, the 37-year-old 110m hurdler only clearing four hurdles before succumbing to a tendonitis injury that has plagued him all season.
The 1996 Olympic champion had been hoping to qualify for a fourth Olympics.