Zlatan Ibrahimovic has been included in Manchester United's squad for the group stages of the Champions League.
The former Sweden striker agreed a deal to rejoin the club last month but is still out of action with a knee ligament injury sustained in April.
There is doubt the 35-year-old will play again in 2017 but manager Mourinho's decision to include him in his European squad - which was not unexpected - would improve United's options should he return ahead of schedule.
United will play Basle, CSKA Moscow and Benfica in Group A. Speaking last month, Mourinho said he doubted Ibrahimovic would be fit for any of the six fixtures but would name him in his squad anyway.
Concerns have been raised over the seriousness of Nathaniel Clyne's back injury after the defender was left out of Liverpool's Champions League squad.
Liverpool can't alter their squad until the knockout stage in February, providing they qualify, which suggests Clyne is likely to be unavailable for the medium term.