Manchester United star Anthony Martial isn't yet fit enough, suggests Jose Mourinho: 'He suffers a little bit with accumulation of matches... his body, his biological situation has space to improve'

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Jose Mourinho has revealed his belief that Anthony Martial is not yet fit enough to cope with playing multiple, full matches in succession.

Martial, 21, scored Manchester United's third goal in the 32nd minute during a superb first half in the 4-2 win at Watford on Tuesday night, but was withdrawn after 65 minutes for Marcus Rashford.

The Frenchman, who joined United from Monaco in 2015 for £36million, a world-record fee for a teenager, has scored eight goals for United this season but has often struggled to win a place in the first team, often swapping forward duties with Rashford.

Anthony Martial celebrated scoring for Manchester United in their 4-2 win at Watford

Martial scored in the 32nd minute but was withdrawn for Marcus Rashford after 65

Mourinho said he was 'pleased' with Martial's performance but went on to discuss his player's decline in the second half of the match before he was substituted.

'I think he suffers a little bit with accumulation of matches,' Mourinho told United's official website. 'I could feel that in the second half he was going down and down and down.

'He’s still a young guy and his body, his biological situation has space to improve but in the first half, during the time, he had strength and explosion in his legs. He was dangerous and [scored] an important goal.'

Martial scored 'an important goal', according to Jose Mourinho, who was 'pleased' with him 

The Frenchman slots in United's third goal at Vicarage Road on Tuesday night 

Mourinho also has fitness concerns over midfielder Nemanja Matic, who was substituted after just 54 minutes at Watford due to a 'muscular' problem.

United are awaiting news on Matic's condition ahead of Saturday's trip to the Emirates Stadium to face old rivals Arsenal. 

Mourinho, meanwhile, was happy with Victor Lindelof's performance at Watford, particularly in keeping the dangerous Richarlison quiet. 

Lindelof has struggled since his £30.7m summer move from Benfica to United, but Mourinho saw this as another step in the right direction for the 23-year-old Swedish defender.

Mourinho said: 'I think Richarlison is a very good player and a difficult player to play against, but Victor is very fast and he’s adapted to play centrally but also to go to the sides because he’s got the agility that many of the central defenders don’t have. 

'I think it was another very positive performance by Victor.' 

But Mourinho has raised doubts over Martial's fitness to play every game for United