The Red Devils forward is thought to have grown frustrated at the lack of first-team options at the Old Trafford outfit over the past 12 months.
Manchester United manager Jose Mourinho has used the France international sparingly in the 2017-18 Premier League campaign.
The 22-year-old has been linked with a potential switch to their Premier League rivals Tottenham Hotspur in recent weeks.
European giants Paris Saint-Germain and Inter Milan have been touted as potential suitors for the France international this summer.
Mourinho is thought to be keen to sign Chelsea FC winger Willian and Real Madrid forward Gareth Bale in the summer transfer window.
Sky Sports News reporter Woods believes Martial has no option but to leave Old Trafford.
“He isn’t going to get a run,” Woods told the Transfer Talk podcast. “He isn’t favoured any more. He will sit on the bench. He has to leave.”
Manchester United ended up in second spot in the Premier League table last term to secure their place in the Champions League.
The Red Devils have signed Shakhtar Donetsk midfielder Fred and FC Porto defender Diogo Dalot in the summer transfer window.
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