United boss Sir Alex Ferguson could be without eight senior players for the game.
Wayne Rooney is expected to miss out with the hamstring injury that sidelined him for Saturday's draw with Stoke and he was among a long list of players who did not train at United's Carrington HQ on Monday morning.
Also absent was Rooney's strike partner Javier Hernandez, who limped off early in the Stoke game with a dead leg.
If Hernandez does not recover in time to face the Swiss outfit, Ferguson will be choosing between Michael Owen, Dimitar Berbatov and fit-again Danny Welbeck in his attack.
But the problems do not stop there for United. Central defenders Jonny Evans (ankle), Chris Smalling (groin) and Nemanja Vidic (calf) also did not train.
That is almost certain to mean Rio Ferdinand lining up alongside youngster Phil Jones, with Antonio Valencia again pressed into service as an emergency right-back as Rafael (shoulder) is out with a long-term problem.
Fellow long-term casualties Tom Cleverley (foot) and Darron Gibson (ankle) have long since been ruled out.
United drew their opening match with Benfica in Lisbon a fortnight ago, while Basle are group leaders after defeating Romanian side Otelul Galati in their first game.