The 22-year-old France global forward, who cost the Red Devils an initial transfer fee of £36 million when they signed him from AS Monaco in the summer of 2015 according to BBC Sport, is one of the best young players in Europe, and there is no doubt over his quality.
Asked about buying another striker this summer, Mourinho continued: "No, no".
There were no crumbs of comfort for either Martial or Rashford but Mourinho, others would contest, is probably best off delivering his critiques to both players in private and away from the cameras.
Rashford has been in good form when he has played this season, netting 12 goals and providing nine assists in all competitions.
Rashford had also questioned his future at the club.
"If I was you, I would go in another direction". "But we always want more and we always want to show progression individually and as a team, so the numbers don't really matter as much as the results do to me".
Rashford said: "I wasn't aware of it before I saw it and it's something to be proud of".
Five Blues up for PFA awards
He leads the assist charts with 15 and has scored 7 goals plus he played his part in winning the League Cup. The victor will be announced at the PFA's annual awards ceremony in London on Sunday, April 22.
Mourinho was even less forthcoming when questioned about Martial's lack of game-time.
The Manchester United manager said in a press conference when asked about Martial's situation: "If I was you I would go why [Romelu] Lukaku plays every match, why [Nemanja] Matic plays every match". The answer is if you want what I call dry answers, I have dry answers. Only 11 can start.
"That is just football".
"It is just football".
"It's just football, we can not have 11 players, it would be incredible economically for the football clubs to have only 11 and play with the same 11, no injuries, suspension, fatigue, it would be better for everyone to have only 11 but is not impossible".
The Red Devils are set to host bottom side West Brom at Old Trafford on Sunday before travelling to Bournemouth. City are 13 points clear of United at the top EPL table.
WEST BROM'S POSITION IN THE LEAGUE "I am surprised". I am surprised because of the quality and experience of numerous players and the squad.