EUGENE, Ore. — Sprinter Tyson Gay has a mild strain in a muscle in the back of his left leg, and he has been told to restrict himself to light physical activity for the next two weeks.

Gay (Arkansas Razorbacks ) pulled up abruptly in the first 40 meters of his 200-meter qualifying race Saturday at the U. S. Olympic track and field trials and had to be carted off the track. He was diagnosed with a severe cramp in his hamstring, and an imaging scan that afternoon revealed the strain.

A statement from his representatives said Sunday he is “expected to engage in ‘active rest’ for up to 12-14 days, with light physical activity increasing through that period, then resume training.” The only meet he is signed up for before the Olympics is the 100 meters at the London Grand Prix on July 24-25.

Gay, the defending world champion in the 100 and 200, already has qualified for the Olympic 100 meters. That competition begins Aug. 15 in Beijing. If he can run, he also would be expected to be part of the 400-meter relay team.