The following is from UFC.com:
Due to late medical licensing issues, Nate Marquardt has been pulled from Sunday’s UFC Live main event in Pittsburgh. Stepping in to face Rick Story on the main card will be Pennsylvania’s own Charlie Brenneman, and the Cheick Kongo vs. Pat Barry bout has been elevated to the main event slot. UFC Live airs on Versus at 9pm ET / 6pm PT.
Shortly after, UFC.com issued a video statement from president Dana White which announced Nate Marquardt’s mysterious release from the UFC.