Darren Clarke has withdrawn from the US Open Championship because of his lack of form and his duties as Europe's Ryder Cup captain.
The Ulsterman, now 670th in the world, has had just one Top 10 finish since he won the Open in 2011.
Fully exempt thanks to that Open win — his five year exemption runs out this year — will be replaced in the field by South Africa's Thomas Aiken, the first alternate from the Memphis sectional qualifying site.
“I’m currently dedicating all of my time to our preparations for the Ryder Cup and unfortunately the U.S. Open is not the place to be when your game isn’t 100 percent,” said Clarke, who has competed in 15 U.S. Opens, with a best finish of T10 in 1999.
“I’m very sorry to miss Oakmont but I’m sure it will be a brilliant week for everyone. I’ll certainly be watching very closely.”
Aiken shot 69-67--136 at Ridgeway Country Club and Germantown Country Club on June 6. He tied for 25th last year at Chambers Bay in his first U.S. Open.
Thailand's Thongchai Jaidee also withdrew for "personal reasons" and will be replaced in the field by Jeev Milkha Singh, of India, the first alternate from the England sectional qualifying site.
Milkha Singh, a 44-year-old, shot 71-71--142 at Walton Heath Golf Club on May 30. He is playing in his fifth U.S. Open. His best finish was a tie for 36th at Oakmont Country Club in 2007.
Ireland will have three players in Pittsburgh next week with 2010 champion Graeme McDowell and 2011 winner Rory McIlroy joined by WGC-Bridgestone Invitational winner Shane Lowry.