The France international took the Premier League by storm last term, scoring 17 goals across all competitions.
However, he has struggled to make an impression on Mourinho this season.
Anthony Martial's camp are fuming with Jose Mourinho
Jose Mourinho has angered Anthony Martial's enoutrage
Manchester United fans react on Twitter to starting XI against Stoke City
Sat, January 21, 2017
Manchester United fans react on Twitter as Jose Mourinho leaves out Anthony Martial and Michael Carrick for the Red Devils' clash with Stoke City
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Manchester United fans react as Anthony Martial and Michael Carrick are left out of the starting XI against Stoke City
The ex-Chelsea boss has so refused to offer an explanation for the striker's absence.
And French website SFR Sport claim Martial's enoutrage are fuming at Mourinho's treatment of the forward.
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Juan Mata's own-goal has put Stoke in front
Today's snub suggests the striker could well be set to leave Old Trafford if he cannot nail down a place in Mourinho's starting line-up.
His replacement for today's game – Juan Mata – has scored an own-goal to give Stoke the lead.