Louis Oosthuizen withdrew from the U.S. Open on Friday.
The former British Open champion pulled out of the championship prior to the start of his second round with an unspecified injury.
Oosthuizen, whose wife is expecting a baby any day now, started the championship with a 5-over 75 on the East Course at Merion Golf Club.
The South African was at his fourth U.S. Open Championship. He missed the cut in 2010 and 2012, while posting his best finish, a share of ninth, in 2011 at Congressional.