Manchester United's players are set to return to training at Carrington on Tuesday - but it is still uncertain whether Michael Carrick will be in charge. United head coach Carrick was at Carrington on Monday to watch the club's U21s take on Hull in a behind-closed-doors game.The first-team players had a scheduled day off but Omar Berrada, the chief executive, and Jason Wilcox, director of football, also met at the training base.