The Red Devils have been linked with a host of players this summer and have brought in three new stars ahead of the start of the 2017-18 campaign.
Manchester United have signed Victor Lindelof, Romelu Lukaku and Nemanja Matic so far as Mourinho looks to steer his side to a Premier League title challenge in his first campaign in charge at the club.
The Red Devils continue to be linked with a number of other stars, including the likes of Ivan Perisic and Danny Rose.
However, the Manchester United manager has insisted that he will not “moan” if his club are not able to bring in another player before the transfer deadline at the end of the month.
Speaking at his pre-match news conference on Friday afternoon, Mourinho said: “I’m happy with the effort the club did.
“I’m happy that the club managed to do 75 per cent of the work before the Premier League starts.
“And if, until 31 August, the remaining 25 per cent don’t arrive, I will not moan. I will just go with everything I have to try to win every match we play.”
Mourinho is currently preparing his team for their Premier League opener against West Ham United on Sunday afternoon as they look to kick off their season with a victory.
The Red Devils finished in sixth place in the Premier League table last term.
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