The Portuguese boss previously hinted that he could be drafted into the Europa League squad, but now believes there is a chance for the 32-year-old to pick up some game time in the Premier League.
He made his first start for Man United since Jan. 9, 2016, after being named in the side to face Wigan Athletic in the FA Cup fourth round on Sunday.
Speaking about his future at Old Trafford, Mourinho insists he can take advantage of the fixture congestion.
“Basti may be a surprise for some as we made that decision not to have him in the squad for a couple of months,” he said.
“Since the moment he’s been back with the team, he’s fighting also for his chances with so many matches as we have now. We’ve the postponed match [at Manchester City] because of the EFL Cup final, the Europa League and the fact that Morgan Schneiderlin and Memphis Depay left the club.
“The squad is shorter and we need him. Today is an opportunity for him to play and show that he is ready – even for the Premier League.”
His last start for United came over a year ago in the 1-0 FA Cup third-round victory over Sheffield United after falling out of favour under Jose Mourinho.
Bastian has made just two appearances from the bench this season and he’ll be hoping to play more of a role after starting against Wigan, especially after picking up an assist for Fellaini’s opener and a goal later on.