U.S. swimmer Jessica Hardy has tested positive for a banned substance, believed to be a stimulant, and expedited arbitration proceedings aimed at resolving whether she will remain eligible for the 2008 Olympics have been launched.

Hardy, 21, was tested at the U.S. Olympic Trials. Both her A and B samples have come back positive.

U.S. swimming national head coach Mark Schubert declined to comment.

"She just all of a sudden was not around," a swimmer on the U.S. team said, speaking on condition of anonymity. "We don't know anything yet. No one knows anything. All I know is we have a team meeting tomorrow."

Hardy finished first in the 100m breaststroke at the Olympic Trials earlier this month, and second in the 50m freestyle. She also qualified for the 4x100m medley relay and 4x100m freestyle relay.

If she's found liable of a doping violation, and if she's then hit with the standard punishment, a two-year ban, the mechanics of how to replace her then come into play.

According to USA Swimming's official selection procedure, no new members can be added to the team after July 21; instead, the vacant spots would be filled with the swimmers currently on the team with the fastest recorded times in those events since Jan. 1, 2006. Those swimmers are Rebecca Soni in the 100m breast and Kara Lynn Joyce in the 50m free.

Hardy broke the world record in the 100m breast in the semifinals at the 2005 Worlds; she went on to finish second in the final. That world record was subsequently broken by Australia's Leisel Jones, but her time still stands as the American record. At the 2007 Worlds, she finished fourth in the 100m breast and won the non-Olympic 50m breast.

Source:Xinhua