Mike Martz says he is retiring from coaching.
The NFL Network first reported his decision this week and Martz told the Chicago Sun-Times, ''It's time.'' He did not return a message left Tuesday.
The architect of ''The Greatest Show on Turf'' as offensive coordinator and head coach of the Rams, Martz spent the past two seasons as the Chicago Bears' offensive coordinator. He had an expiring contract and left after what were described as philosophical differences.
The Bears finished 8-8 after season-ending injuries to quarterback Jay Cutler and running back Matt Forte. Martz is best remembered for his time in St. Louis, where he helped the 1999 team win a championship as offensive coordinator under Dick Vermeil and the 2001 team get back to the Super Bowl as head coach. Bears coach Lovie Smith was his defensive coordinator.