The Belgian, who has made just one start since September due to recurring knee problems, lasted just eight minutes of Man United’s 2-0 defeat at Wembley before being forced off.
Reports after the game suggested that Fellaini could be out for up to two months amid fears he had done damage to his medial ligament, which would require surgery.
Speaking at a press conference ahead of the clash with Huddersfield Town, the 55-year-old was unable to confirm whether Fellaini would require surgery but was notably pessimistic about his return date.
“I don’t have good news,” he said. “I don’t have news because I don’t want to give news based on an initial approach but I don’t think the news is very good, he has a problem in his knee, is the same knee but not the same local, was internal, now external, so let’s wait a couple of more days but out of the game tomorrow.”
“Is not an ACL, a complete rupture of any structure of the knee, we are not going so far as that but we need him, CL is arriving and lots of tough matches to play and probably we are going to lose for a few weeks. Two, three four or five, I cannot say at the moment.”
The positive news, I guess, is that Fellaini, while injuring the same knee as before, has not re-aggravated the issue that was keeping him out to the point where surgery is required.
But the bottom line is still decidedly grim: that knee problems, once again, will keep Fellaini – such an important component to United’s positive start to the season – out for an extended period of time, increasing pressure on the likes of Paul Pogba and Nemanja Matic to deliver and, just as importantly, remain fit.