HOUSTON — Paul Hamm's stay at the top of the U.S. gymnastics championships might be a short one.

Hamm said he might not compete Saturday after injuring his right hand in the last few seconds of his parallel bars routine, his final event of the night Thursday. As Hamm was flipping to do work on one bar, his right fingers caught on the rail and were jammed to the side. He fell off and immediately grabbed his wrist as he grimaced.

The Olympic trials are June 19 to 22 in Philadelphia, and Hamm is considered the only lock to make the team — even if he's not at trials.

Even with the injury, the defending Olympic champion had a commanding lead on his fellow Americans. His score of 93.450 was more than three points ahead of Joseph Hagerty, who had 89.750.

Also, three-time Olympian Blaine Wilson's comeback ended after two events when he withdrew.

The 33-year-old Wilson, who won the all-around national title five straight years from 1996-2000, then said he was through with the sport.

Wilson scored a 14.00 on the horizontal bar, then got a 13.20 in floor exercise before he walked away with little fanfare.