Shaw has not played in the Premier League or Champions League yet this season and United were believed to be preparing to sell the left-back in January.
Mourinho insisted Shaw would be given another chance at United despite transfer reports linking him with Tottenham and Newcastle.
Shaw has suffered from fitness issues for two seasons, but Mourinho said he was impressed with his renewed commitment.
‘I’d have to think. I’m going to make a few but not too many changes,’ said Mourinho when asked about Shaw.
Manchester United 2017/18 Fixtures
CSKA Moscow (H) – Tues Dec 5 (Champions League)
Manchester City (H) – Sun Dec 10
West Bromwich Albion (A) – Sun Dec 17
Bristol City (A) – Wed Dec 20 (EFL Cup)
Leicester City (A) – Sat Dec 23
Burnley (H) – Tues Dec 26
Southampton (H) – Sat Dec 30
Everton (A) – Mon Jan 1
Stoke City (H) – Sat Jan 20
Tottenham (A) – Wed Jan 31
‘We didn’t qualify yet and I need to keep a certain balance in the team. But when you speak about Luke Shaw, you are right.
‘He’s working to have an opportunity and sooner or later, the opportunity will arrive, because he deserves that opportunity.
‘Selected for tomorrow, yes, for sure. To start or to be on the bench, I cannot answer.’
United need to pick up at least a point against CSKA after their surprise defeat to Basel in their last game.
Shaw could be handed a lifeline by Mourinho and the chance to turn back the tide with the January transfer window bearing down on him.
United want to spend in the coming window and will need to trim their squad to make space for new faces.
Shaw has made just 49 appearances for United since joining from Southampton in 2014.
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