Manchester United's defensive worries deepened on Wednesday when Chris Smalling was at the centre of another injury scare.

Smalling is understood to have hurt his thigh in training ahead of Saturday’s Premier League clash with West Ham at Old Trafford.

United will assess his condition on Thursday with Louis van Gaal waiting anxiously to see if the England defender will be fit to play.

Louis van Gaal is sweating on Chris Smalling's (above) fitness ahead of West Ham clash

United are already without central defenders Phil Jones, Tyler Blackett and Jonny Evans (C)

But it was the last news the United boss wanted to hear having already lost three centre-backs to injury and suspension.

With Phil Jones sidelined due to a hamstring strain, Jonny Evans limped out of Sunday’s shocking 5-3 defeat at Leicester City after hurting his ankle before Tyler Blackett was sent off.

Van Gaal had wanted to pair Smalling with Marcos Rojo in the middle against West Ham

United need to get their campaign back on track after the demoralising 5-3 defeat to Leicester

VIDEO United can still be successful

Smalling replaced Evans at the King Power Stadium, making his first appearance after a month out with a groin problem, but could not prevent United conceding four goals in 21 minutes in the second half.

The extent of his latest injury was unclear last night but United are banking on him recovering in time to play alongside Marcos Rojo in another new central defensive pairing against the Hammers.