United handed the Premier League title to rivals City with defeat to West Brom, and Mourinho revealed after the game that other players will be given a chance to prove themselves against Bournemouth on Wednesday.
He accused his players of resting on their laurels after beating City two weeks ago.
"Rotating is not the right word", the manager said. "In that semi-final, they are having one day extra to us to recover so I need also to think about that".
The Telegraph have reported that, in particular, Alexis Sanchez, Paul Pogba, Juan Mata and Ander Herrera are all in danger of being left out the squad to face Spurs weekend, as Man United prepare for what is now the biggest game of their season. This is an opportunity for some people to play and to try to get a place in the team.
"What is the criteria for managers to choose a team?"
'The commitment, the desire, and I asked if Pogba can do that all the time, the way he played against City. This is the only way I can select players.
Still smarting after United's loss to West Bromwich Albion, a furious Mourinho, declared "the price they cost, their salary, their handsome face" doesn't guarantee a place in his team.
'He told them be careful it is going to be different against West Brom and I go back to Pogba: why didn't you and the rest of the team do what you did against City all season? "And he had a yellow card so he was in a more hard position than others".
Manchester Evening News is reporting that Mourinho wants to see his team go a goal down just to see how they respond.
Mourinho said the risk of a red card was partly why Pogba was replaced but stressed the France global was no worse than some of the players who played the full match. "The only way is to go with performance".
Instead, Mourinho accused his players of being "masters in complicated football", trying too many tricks and flicks and taking one too many touches against supposedly inferior opposition, who won via Jay Rodriguez's second-half header from a corner despite United dominating possession.
Juventus would happily provide a home for both, but whilst they've got a very good chance of signing Darmian, with that looking like a transfer which could soon happen, Martial is going to be much more hard.