US world 100 metres silver medallist Tyson Gay had an arthroscopic procedure on his injured right hip and will not run again this year, his manager said on Thursday.
Gay, the world's second fastest man behind Usain Bolt, had the surgery on Tuesday in Vail, Colorado, Mark Wetmore said in a statement.
"The doctor was pleased with the outcome and believes Tyson will resume his normal base training in the fall as he prepares for 2012," said Wetmore.
The frequently-injured Gay had hoped to race Jamaica's Bolt in August's world championships but was forced to withdraw from the US world trials 100 metres semi-finals last month because of the hip injury.
He will now focus on recovering and preparing for the 2012 London Olympics and an anticipated showdown with Bolt.
"The procedure, which addressed an impingement in his hip, went just as expected - with no surprises or complications," Dr. Marc Philippon said in a statement. "Tyson is already doing range-of-motion, active rehabilitation and I expect him to resume normal training after six-to-nine weeks."
Gay, who turns 29 on August 9, was not available for comment.