Both were substituted with knee injuries during United's Europa League extra-time win over Anderlecht yesterday.
"We played a very good match".
The 19-year-old forward proved the hero on Thursday, settling their fiercely contested clash with Anderlecht with a clinical extra time finish.
Former United skipper Roy Keane suggested that snub from Mourinho was the "final nail in his coffin" at Old Trafford, but Rooney could now be asked to fill the void left by Ibrahimovic's absence.More news: J.R. Smith Leaves Game 2 With Left Hamstring Injury
"I can't do that because I am a manager not a doctor", Mourinho said. "But he has the experience and character, so he has to". I even have to think that Axel Tuanzebe goes to the Under-Something World Cup in Korea, because maybe Axel has to come now.
United do not yet know the full extent of the injuries, but Mourinho is not optimistic and is certain neither will feature in Sunday's Premier League clash against Burnley. They will receive their semi-final draw tomorrow at midday.
However, Zlatan Ibrahimovic and Marcos Rojo picked up injuries trying to win the ball in the course of the game.
"It proved to be a tough match, a tough adversary, I'm tired, I picture the players tend to be more exhausted than me", he said. "If one day it is not mathematically possible we have to put everything in the Europa League because the Europa League is an important title, and on top of that the bonus of playing in the Champions League". Ashley Young is fresh to play. No problem if you need to make a change in another position do it because I am ready for it'.More news: Lined Up: Game #4 @ Bruins
The former Paris Saint-Germain striker, scorer of 28 goals this season, was able to hobble down the tunnel, aided by medical staff, but United's fans will fear they have seen the last of him this season.
"That is why I kept Marcus on the team the whole time - for months he was not scoring a goal, but my trust in the boy is always based on his mentality. But the power is in their (the Football Association s) hands".
"No. Nicky Butt [United's head of Academy] doesn't pick him to play that game".More news: Four Adjustments For Hawks Going Into Game 2
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