He was left off the list submitted to UEFA and will not be able to play for Man United against Fenerbahce, Feyenoord and Zorya Luhansk in the group stages.
UEFA regulations claim a club can only have 21 players who are not club trained in their 25-man squad, United have 22 non-club trained players which resulted in Schweinsteiger being left out.
Wayne Rooney and Jesse Lingard are the only two players who meet the requirement to qualify as a club-trained player after spending more than three full seasons at Old Trafford between the ages of 15 and 21.
Bastian was deemed surplus to requirements by Mourinho and was training with the reserves team, although he was listed in United’s Premier League squad, the Portuguese boss claimed it would be difficult for him to play again.
Mourinho has now made it clear he is not a part of his plans for this season and he has dropped to the bottom of the pecking order under Paul Pogba, Michael Carrick, Morgan Schneiderlin, Ander Herrera and Marouane Fellaini.
It seems almost impossible for Schweinsteiger to make it back into United’s first-team now as Mourinho has prove how little faith he has in the Germany world cup winner.