Mark Wahlberg is set to star as Col. Steve Austin, a downed pilot who is saved by an operation that makes him part machine, in the long-awaited big-screen adaptation of the classic 1970s sci-fi TV show.

The movie is slated to begin shooting this summer and, despite the loss of director, the studio is intent on keeping its schedule and will immediately look for a filmmaker.

One candidate may already be in the wings: Mel Gibson has already been circling the part of Oscar Goldman, the government mentor of Austin. Gibson, who has been developing a World War II naval thriller as his next project, could be conscripted into hopping into the pilot’s seat for Six Billion Dollar Man.

"Creative differences" are being blamed for the exit of Szifron, but the exact nature of the rift remains unknown.

Szifron boarded Six Billion Dollar Man three years ago when the project was in development at The Weinstein Co. Warners picked up the rights from TWC late last year — for a reported $7.2 million — as the beleaguered company was shedding assets to keep the lights on.