The Portuguese opted to start Victor Lindelof alongside Chris Smalling at the heart of the United defence against the relegation-threatened strugglers, with Bailly not even featuring in the squad.
However, there is no injury fear for the Ivory Coast international and Mourinho is simply keen to rotate his squad ahead of a busy week of football, which also sees them face Bournemouth and Spurs.
When asked why Bailly was absent from the squad, Mourinho replied: A decision again.
Victor played the match against Swansea at home and it was very suited to his qualities.
Normally, we are going to have more of the ball and, normally, its when we need somebody from the back to add extra technical quality in the middle of the back [four].
We have three matches in a week. Bournemouth in a few days [Wednesday night] then Spurs after a few days again.
In that semi-final, they are having one day extra to us to recover so I need also to think about that.
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