Michael Phelps is almost done at the U.S. Olympic swimming trials. But the superstar has one bit of unfinished business: the 100 butterfly and a showdown with world recordholder Ian Crocker.

Phelps must finish first or second tonight to ensure he swims eight events at the Beijing Olympics. Then he'll need to win them all to surpass Mark Spitz's record of seven gold medals in 1972.

Phelps heads into the final as the fastest qualifier with a time of 51.10 seconds. Crocker, who set the world mark three years ago, was second-best in 51.52.

Those two, along with Georgia swimmer Gil Stovall, were the only men under 52 seconds in the semifinals.

Every time Crocker has beaten Phelps in a 100 fly final, he's set a world record, including against Phelps at the 2004 trials.

Courtesy: Associated Press