Ralf Rangnick held a one-on-one training session with a Manchester United player only for his instructions to be entirely disregarded, according to reports.
The German, 63, is still battling to mould the squad to his requirements having been appointed interim manager at the end of November.
Although the Red Devils secured a morale-boosting victory over Leeds United on Sunday, results have been mixed on the whole to leave their hopes of Champions League qualification teetering.