Despite an exciting start to life at Old Trafford, Martial has stagnated and found himself out of manager José Mourinho’s favour.
Allardyce has criticised Martial over his consistency at United and wonders what United have seen to offer him the new long-term contract.
“I’m very surprised if they have offered him a five-year contract in all honesty,” he told talkSPORT.
“The lad is in his fourth season at Manchester United and I don’t think anybody would actually say he has delivered consistently.”
Martial joined United from Monaco in 2015 for £54m and made headlines after a glorious solo-effort during his debut against arch-rivals Liverpool FC.
Martial went on to score 17 goals in all competitions in his first season with United but has only managed a combined 19 in the two seasons since.
It is this backwards progress that Allardyce is referencing when he says he is surprised United have offered Martial such a long contract.
Times are turbulent at Old Trafford, and there were many rumours that Martial would leave United in the summer.
Manager José Mourinho is involved with a public spat with United’s executive vice-chairman Ed Woodward and on the pitch, they have lost two games already this season.
Mourinho supposedly does not fancy Martial, which has led to much speculation about the Frenchman’s future away from the club.
Martial signing a massive contract extension certainly came as a surprise, and immediately rumours started to circulate that Martial felt he could outlast Mourinho at United.
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