Rio Ferdinand and Peter Crouch are unsure whether Ralf Rangnick is the right man to fix Manchester United's problems.
Rangnick was brought in as a temporary replacement for the sacked Ole Gunnar Solskjaer in December, taking the reins until the end of the season.
After that, the German will take up a consultancy role and United will then move to hire a permanent boss, with Mauricio Pochettino and Erik ten Hag the current front-runners.
