While the 24-year-old has scored 73 goals in 229 games for United, he is yet to find his scoring touch for France, having scored just once in 19 international appearances so far.
But Deschamps is happy with the forward’s development at United, which Martial has represented since 2015.
The France coach praised Martial’s performance in Saturday’s 1-0 win in Portugal, saying he has developed a winning mentality.
“It lacked finishing – it looked a bit awkward,” admitted Deschamps in an interview with TF1 .
“But honestly, after reviewing the moments, it came down to small margins.
“He’s part of the group of players who haven’t been here for a long time, but he’s changed during this time, on and off the pitch.
“Over the years, it has also matured. He is much more determined – he already had quality. Things are more concrete.
“I feel a little unhappy for him because he was not rewarded with a goal, but he is very promising. ”
Although he has yet to score in the Premier League this season, Martial has scored twice in the Champions League and had three assists in both competitions.
He hopes to stand out when United host West Brom on Saturday, who look to build on their 3-1 win at Everton ahead of the international break and end their home hoodoo.
Ole Gunnar Solskjaer’s side are yet to win a top-level game at Old Trafford this season, having lost to Crystal Palace, Tottenham and Arsenal and held to a draw by Chelsea.
United beat RB Leipzig at the Theater of Dreams last month and hope to extend the Baggies’ miserable five-game losing streak from their first eight games.
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