Manchester United manager Jose Mourinho said he was preparing for bad news after losing Zlatan Ibrahimovic and Marcos Rojo to injury during his side's Europa League quarterfinal success against Anderlecht.

"I want to wait, but my feeling is not good for both," Mourinho told reporters after his side's 2-1 extra-time win at Old Trafford on Thursday completed a 3-2 aggregate victory.

"I want to wait and I want to try to be optimistic, but I'm not."

Centre-back Rojo was stretchered off with a leg injury in the first half, while Ibrahimovic, United's 28-goal top scorer, hobbled off in stoppage time after his right knee bent the wrong way.

Mourinho said he expected to find out more about the two players' injuries within "a couple of days".

Marcus Rashford proved a capable deputy for Ibrahimovic, netting a smartly taken winner to send United into the competition semi-finals for the first time.

The 19-year-old had also scored the opening goal in United's 2-0 win over Chelsea on Sunday after Ibrahimovic was rested.

Daley Blind took over from Rojo, but Mourinho has fewer options in central defence, with Chris Smalling and Phil Jones both currently sidelined.

The pair sustained injuries on England duty a month ago, Smalling injuring his knee and Jones his foot.

Mourinho said both players would be able to come back sooner than anticipated if they put their minds to it.

"I think it's time for Jones and Smalling to be brave, to risk," said the Portuguese, whose side visit Burnley in the Premier League on Sunday before tackling Manchester City next Thursday.