Marcus Rashford limped off for United in the 1-0 win over Wolves.
He was originally rested by United before being brought on midway through the second half.
Rashford seemed to make an impact, with United scoring just three minutes later through Juan Mata.
But then potential disaster struck, as he limped off with an injury moments later.
This came at the worst possible time, with an even bigger match upcoming on Sunday.
Rio Ferdinand spoke for United fans around the world with his reaction.
Rashford has 19 goals this season in all competitions and has become irreplaceable.
United looked flat without him and it was no coincidence that we scored minutes after he came on.
He lasted just 16 minutes before being substituted for Jesse Lingard.
He unsettles defenders, and has had success against Liverpool in the past, scoring against them this season.
Rashford was taken off as a precaution, but if he is missing this weekend it will be a major blow for us, and would just sum up the luck Liverpool are having this season.
Let’s hope he makes a very swift recovery and is 100 per cent on Sunday.
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