Clay, a Castle High School graduate, dropped out after four events today. He still can compete at the world championships in Osaka, Japan, because he is the defending champion. He only had to show up to compete in any event at the U.S. meet to qualify for worlds.

He cited no big health problems, just a few minor dings from the decathlon he completed at the Hypo Meeting in Goetzis, Austria, on May 27.

"A little bit of knee pain, stuff like that," he said. "It wasn't there today. My body wasn't feeling quite up to par. There were some things that were a little off. We were just coming to work out anyway here. It's probably better to go home and work out. We don't want to risk any injury."

Clay was second to defending U.S. champion Tom Pappas when he withdrew.

A year ago, Clay pulled out after seven events because of low blood sugar. He was the Olympic silver medalist in 2004 and won the U.S. title in 2004 and 2005.