The 22-year-old has seen a decline in the number of first team appearances following Alexis Sanchez's arrival in January.
Mourinho only offered "dry answers", however.
Martial, meanwhile, has started 16 Premier League games but none since February, although he has been sidelined due to injury, with both forwards hoping to be selected for the World Cup.
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Jim Lo Scalzo-Pool/Getty ImagesThe release of the "Access Hollywood" tape threw President Donald Trump's campaign into a tailspin. Renato Mariotti , a former federal prosecutor in IL , elucidated the difficulty of differentiating between the two.
After declaring Sergio Romero the only player unavailable against West Brom, Mourinho faced questions over Martial.
"If I was you, I would go why Lukaku plays every match, why [Nemanja] Matic plays every match, you always go to the one [who doesn't play]".
The 20-year-old, born and raised in Wythenshawe, south Manchester, feels being a local boy in the United squad gives him the motivation to go an extra mile playing for the club.
"It would be fantastic economically for the football clubs to have only 11 and play with the same 11, no injuries, no suspension, no fatigue", Mourinho said. And a dry answer is only 11 can start the match and we are 22.
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He was signed by the Jacksonville Jaguars in 2014 and has also spent time with the Philadelphia Eagles, Indianapolis Colts. Seattle recently cut Trevonne Boykin, their backup quarterback to Russell Wilson , over allegations of domestic violence.
While only Romelu Lukaku has played more than the 43 games the England global has started for his club, just 22 of those have come from the beginning of games.
"I am surprised the quality, the experience of numerous players, the squad, the stability of the past years, is a surprise for me they find themselves in this position", Mourinho said during his pre-match press conference on Friday.
Having discovered that City players had booked tables in top Manchester restaurants for after the game to toast their Premier League success, United's stars couldn't resist a jibe or two. If United can cut loose more often, fans and media may not grumble as much about the personnel.
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Germany's Angela Merkel said it was "obvious" that Syria hadn't eradicated its chemical arsenal as it had earlier claimed. And we'll see what happens, folks.