Lukaku was forced off early in the second half after coming off worse in a challenge with young Arsenal defender Konstantinos Mavropanos.
The Belgian striker is Manchester United’s top goal-scorer this season and he has been earning plenty of praise for his strong performances since his move to Old Trafford from Everton last summer.
Manchester United fans will clearly be hoping that Lukaku will be able to return to action as soon as possible as the Red Devils look to secure second spot in the Premier League.
Mourinho’s men are also set to take on Chelsea FC in the FA Cup final later this month as they bid to try and end the campaign on a high by winning a trophy.
And Mourinho delivered the latest update on Lukaku after the victory over Arsene Wenger’s men at Old Trafford.
Speaking at his post-match news conference, Red Devils boss Mourinho said: “I don’t know if he is going to be out or if he’s not OK.
“He wants to play all the time. He is never tired and, when he has small things, he doesn’t care. He still wants to go.
“So, for him to say immediately, to change him, it is because he couldn’t play. But there are three more weeks until the final, so let’s see. I know it was on his foot but I don’t know more yet.
“I don’t think it’s something, or I hope it’s not, that in this moment keeps him immediately out of a game that is in three weeks’ time.
“But I don’t know. I never, when I finish a game and a player is injured, immediately go for good or bad news. I wait a bit more.”
Manchester United will return to Premier League action on Friday night when they travel to Brighton and Hove Albion.
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