It is understood that Ferguson will remain in the job until at least the end of next season but the club has put a short-list in place and ex-defender Blanc has emerged as the frontrunner.
A United insider confirmed that Blanc was being considered for the job down the track and said his relationship with Ferguson, whom he ended his playing career under at Old Trafford, was a key factor.
"Replacing Sir Alex will be the toughest job since Matt Busby left the club," the insider said.
"It isn't just about winning at United. It's about playing the game the right way and upholding the traditions.
"There is a lot of admiration at Old Trafford for the job Blanc has done at Bordeaux and the style of play he has imposed.
"It is no secret at the club that he became close to Sir Alex when he was a United player. There is still a lot of mutual respect."