Martial suffered an apparent hamstring injury in the second half of Uniteds 2-2 draw against Arsenal on Wednesday.
Jose Mourinho initially played down the severity of Martials situation, describing it as a pre-injury and that the player had only felt tightness in his muscle.
But before his sides training session on Friday, Mourinho admitted that Martial was considered a doubt for the game against Fulham at Old Trafford and his availability would depend on how he would get on in the session.
And it appears Martial will not be risked against Claudio Ranieris side as he did not arrive at The Lowry Hotel with the rest of Uniteds players.
Eric Bailly, who impressed in the draw against Arsenal earlier, was also not seen arriving with Uniteds squad and is now considered a major doubt to feature against Fulham.
Before facing Arsenal, the Ivory Coast international had not started a game for United since he was forced off after 19 minutes in the 3-2 win over Newcastle United on October 6.
In a boost for Mourinho, both Chris Smalling and Phil Jones were with the squad on Friday evening after being labelled as doubts on Friday morning.
Romelu Lukaku and Paul Pogba are also in the matchday squad after being dropped against Arsenal.
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