Michael Turner -- 'Pretty Sure' I'll Sign with NFL Squad in 2013

Michael Turner's days in the NFL ain't over yet ... the ex-Falcons running back tells TMZ he's "pretty sure" he'll return to the field in 2013.

31-year-old Turner was leaving LAX Monday when we asked if he's found a new squad after parting ways with Atlanta after the 2012 season.

"I'm still relaxing right now," Turner said ... "Still waiting."

Doesn't seem like he's gonna have to wait long -- sources connected to the 2010 and 2011 NFC rushing leader tell us there's real interest from "multiple teams."

We're also told Michael's been busting his incredibly large ass in the off-season and feels back to his old self after suffering groin and elbow injuries last year.

We also asked Turner about Tim Tebow in New England -- Turner suggested we should be more concerned about Tom Brady.