Manchester United vs West Ham: Paddy McNair could be handed debut as Louis van Gaal manages injury crisis

19-year-old McNair is on stand-by should Chris Smalling fail to prove his fitness for Saturday's encounter

Van Gaal was dejected as United stumbled defensively in the second half

Manchester United are so severely depleted in defence that Louis van Gaal is reported to be considering a shock call-up for 19-year-old Paddy McNair from the Under-21’s.

With the news that Chris Smalling is facing a race to be fit for Saturday’s visit of West Ham, Van Gaal is left with limited options to fill the two vacancies in central defense. Phil Jones and Jonny Evans are already ruled out with injury, with the England international suffering a hamstring tear and the Northern Irishman suffering an ankle injury in the 5-3 defeat to Leicester.

Tyler Blackett, who only received his first call-up to the United squad this season after loan spells with Blackpool and Birmingham, is also out of the match against an in-form Hammers side after he was sent-off at the King Power Stadium. With Daley Blind and Marcus Rojo tipped to fill in at the back, Luke Shaw looks set to come in on the left for his first appearance since completing his £27m move to United from Southampton early in the summer.

However, Van Gaal has made it clear that he sees Blind as a defensive midfielder at Old Trafford, and he could choose to call on McNair to partner Rojo with Rafael retained at right-back even though he gave away a penalty last weekend.

The news will cause further questioning of United’s transfer policy in the summer, which saw them considerable strength in attack yet fail to replace Nemanja Vidic and Rio Ferdinand. The veteran defensive pairing saw their contracts run down and were allowed to leave on a free transfer, but the failure to add a quality centre-back has left United horribly exposed throughout the start of the season.

Smalling suffered a thigh injury in training this week (Getty Images)

So what do we know about McNair?

The 19-year-old hails from Ballyclare in Northern Ireland, and joined United at the start of the 2011-12 season where he played among their youth ranks. McNair went on to sign as a third-year scholar at the start of the 2013-14 season, and has since become a regular in United’s Under-21’s.

McNair could be called up in the absence of Jones, Blackett and Evans (Getty Images)

He arrived at United as a natural midfielder, but was switched to centre-back in 2012/13 by Paul McGuinness when he endured his own injury problems with the youth team. McNair, like United team-mate Phil Jones, can play either as a centre-back or a defensive midfielder and he could be called upon for the visit of the Hammers.

McNair featured for United’s Under-19’s in the Uefa Youth League that year, but suffered the shame of being sent-off in his first appearance in Europe against Bayer Leverkusen after picking up two yellows cards.

However, McNair bounced back from his dismissal to force his way into the Under-21 side, and under the guidance of manager Warren Joyce, he tied down a regular spot that has led to him catching the eye of Van Gaal.