The 24-year-old, who has slipped out of England contention ahead of the European Championships, has been left out by Mourinho for much of the current Premier League season.
Alli was handed a rare chance to impress as the Portuguese boss shuffled his team around against Marine in the FA Cup, and he was left satisfied by the performance.
Although Mourinho admitted that is was not the right game to make an assessment of his current ability, he has insisted that his team went into the game with the right attitude.
Mourinho said of Alli: “He was here today and of course it was not the match to measure the quality.
“But the professionalism and attitude and I am very happy with it.
“I will not be surprised if next Wednesday Dele is playing with us.”
Spurs, who were due to take on Aston Villa on Wednesday, could now end up playing a rescheduled match against Fulham following a string of positive tests for Dean Smith’s side.
Mourinho added of Alli: “I am really happy with his attitude in the game.
“Of course we didn’t want to risk much, the pitch is a bit dangerous and their enthusiasm can put the creative ones in some risk.
“But I am happy – good professionalism, good dynamic from him and Gedson (Fernandes) to start trying to create, so really pleased for the performance.”
He then said when asked if he thinks the game against Villa would go ahead: “Yeah.
“Nobody told me that I’m not going to play so tomorrow morning we start to prepare for that game, and the same Tuesday unless somebody tells us different.”