Manchester United defenders Chris Smalling (hamstring) and Jonny Evans (calf) are set to miss Wednesday's key Champions League tie against Olympiakos at Old Trafford.
Both players missed training at United's Carrington training ground on Tuesday where manager David Moyes tried to put to bed reports of a rift between himself and senior players by taking full part in the practice session.
However, Moyes remains under a harsh spotlight that will only intensify if United fail to overturn a 2-0 first leg deficit in their last 16 tie against unheralded Greek side Olympiakos.
And there was further embarrassment for United with the lacklustre manner of their 3-0 home loss to bitter rivals Liverpool on Sunday.
That defeat left English champions United in seventh place in the Premier League, 12 points off a top four finish that would qualify Moyes' men for next season's Champions League.
An exit from the Champions League would effectively end United's campaign, given their unexpectedly early departures from both the League and FA cup competitions.
However, United have repeatedly insisted Moyes, the chosen successor of former boss Alex Ferguson, British football's most successful manager who retired from the Old Trafford hot seat at the end of last season before handing over to his fellow Scot, is not under threat.