INDIANAPOLIS— Defensive tackle John McCargo wanted a fresh start. He won't get it with the Indianapolis Colts.

McCargo failed his physical, voiding the trade that sent him from the Bills to the Colts and sending his rights back to the Bills, Colts spokesman Craig Kelley confirmed Wednesday night. The Buffalo News, citing two league sources, reported on its Web site that the Colts found a bulging disc in his back, a detail Kelley could not confirm.

It was a stark contrast to the way Wednesday started, with Colts coach Tony Dungy welcoming the addition of McCargo and talking about how a new system could make him more effective than he was in Buffalo.