The Chile international has been getting used to life at Old Trafford since completing his move to the club from Arsenal last month as part of the same deal which saw Henrikh Mkhitaryan move to The Emirates.
Sanchez scored his first goal for Manchester United last weekend when he netted the opener in the 2-0 victory over Huddersfield at Old Trafford.
The 29-year-old is likely to be a regular fixture in the Manchester United team between now and the end of the season as the Red Devils aim to try and finish as highly as possible in the Premier League table.
And Mourinho has admitted that he has been thrilled by Sanchez’s application and attitude since his arrival at Old Trafford from Arsenal last month.
Speaking at a news conference at Carrington on Friday, Mourinho said: “His mentality [I particularly like].
“I like to have in my team a player that loses the ball in minute 91 and doesn’t stop until he recovers that ball – even if he is that tired like he was in the last minute of the last match [against Huddersfield].
“A crucial moment in football is when your team loses the ball and you become exposed and open for the opponent to hurt you.
“So when you have players in the team with that mentality of, ‘I made a mistake or I lost the ball and I am going to recover it for my team’, that is very important.
“All of this combination – his experience, his talent, his mentality – makes a player that I like.”
Manchester United are next in action when they take on Huddersfield Town in the fifth round of the FA Cup on Saturday afternoon.
The Red Devils finished in sixth place in the Premier League table last season but won the Europa League and League Cup under Mourinho.
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