Rashford is set to feature in England's squad for the 2018 FIFA World Cup in Russian Federation and might be granted a more prominent role than expected as Gareth Southgate waits to find out the severity of the ankle injury Harry Kane suffered during Tottenham's 4-1 win over Bournemouth on Monday (AEDT).
Rashford scored twice in his first Premier League start of 2018 as United edged out Liverpool 2-1 on Saturday, but Mourinho still substituted the 21-year-old England forward 20 minutes from time as he looked to make the game safe.
In response, Mourinho said: "I read something, some quote from the worst manager in the history of the Premier League - Frank de Boer".
"Tomorrow is a very hard match, playing against a team that didn't lose against Liverpool home or away [in the group stage], that drew in Liverpool and I say Liverpool because they are an example of a very good team in a big stadium with a big tradition".
Maybe with him, he would learn how to lose.
"We try to give the best to the kid's education". Marcus I have to be honest and give the credit to the people of the academy that were responsible for his formation and to Van Gaal for his first season in the first team.
The Portuguese criticised De Boer, who had said on BT Sport that "it is a pity" Rashford plays under Mourinho.More news: Team USA's Can't-Miss Paralympic Event For Saturday, March 10
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"Mourinho is not like that, he wants to get results". Not many were expecting him to start against Liverpool and he had a good match, not just about scoring goals. "He's very young. He needs games, he's so talented - you want to see this player every week". There are only 11 players that can start - it's just one of the those things. "I don't think we're among the five candidates to win the competition".
Paul Pogba remains a doubt with a leg injury picked up in training last week.
Michael Carrick has confirmed he will retire at the end of the season.
"You have to be ready when your chance comes", he declared.
Carrick is expected to join United's coaching staff in the summer.
The 36-year-old expanded on the heart condition he had in September. "When the ball fell to me for the second, I was sure it was going to go in".