The French striker’s future has been a source of speculation in recent months due to him having failed to hold down a regular spot in the first team under Mourinho last season.
It had been suggested earlier in the summer that Martial could be heading on loan to Inter Milan as part of the deal to bring Ivan Perisic to Old Trafford this summer.
However, the 21-year-old came off the bench to score one and set up another in Manchester United’s 4-0 thrashing of West Ham United last weekend.
And, speaking ahead of the Red Devils’ trip to Swansea on Saturday, Mourinho underlined his stance that Martial could be set to play a key role this season.
Speaking at his pre-match news conference on Friday, Mourinho said: “I have faith in him.
“Probably, the player I was looking at [in the transfer market] was not a pure winger, because I have pure wingers.
“The player I was looking for would allow me to play three at the back and do the wing-backs. As a pure attacking player, Martial is a good player.
“He is one of the players who will have a better season than last season. I look at my players and I am sure some will be better than they were last season, and Anthony is one of those, for sure.”
Manchester United have been linked with a host of new players in the summer transfer window but the Red Devils have so far only concluded deals for Victor Lindelof, Romelu Lukaku and Nemanja Matic.
The Red Devils are aiming to improve their Premier League form this season after they finished sixth in the table last term.
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