United fans' love of their young talent was highlighted to Mourinho as the Old Trafford faithful booed when he brought off Rashford instead of Romelu Lukaku for Anthony Martial in the 1-0 win over Tottenham.
However, runaway leaders Manchester City have built up an eight-point gap to their neighbours and Mourinho suggested that their title rivals may be better equipped to succeed than his side.
That is because the player is unable to get a consistent run of games in the Premier League even after some big performances off the bench. But none of them are important.
"I want to see this next weekend if the players that were not going to the national team, I want to see if they are going to play".
McTominay is yet to make his Premier League debut for the Red Devils but has won six caps for United so far, representing the Reds in two Premier League games last season.
"We have the group of players which are the ones that we hope will recover as soon as possible", Mourinho told MUTV earlier this month.
It's certainly going to take something special for Jose Mourinho's to stop Manchester City in their current form. In Ajax I didn't have it. I feel like a ten and I stand for number 10.
Jamaal Lascelles hobbled out of the Bournemouth game, giving Ciaran Clark another opportunity, while Paul Dummett is back in training and would represent a serious upgrade on Javier Manquillo if he is fully fit in time for Saturday.
Newcastle's main concern this term has been scoring goals, with captain and centre-back Jamaal Lascelles currently sitting level with centre-forward Joselu as the Magpies' leading goalscorer on just two.
He hinted at his involvement in Zlatan Ibrahimovic's return and also suggested he prevented Thomas Lemar from joining Arsenal.
In fact, the manner in which he provided an assist within the box to Lacazette was nothing shy of magical.
"It is more difficult now than it was before, but I think it is good".
Mourinho has evaded questions about extending his contract at United beyond June 2019 after flirting publicly with Paris Saint-Germain last month.