Ole Gunnar Solskjaer says Harry Maguire will "bounce back" after his torrid start to the season but could miss Saturday's Premier League trip to Newcastle through injury.
The 27-year-old - the world's most expensive defender - has struggled for Manchester United since a well-documented Greek court case in August.
Maguire was given a suspended 21-month sentence for a range of charges, including assaulting a police officer, when on holiday in Mykonos. However, that sentence has been nullified until an appeal and a retrial in a higher court.
On Wednesday he was sent off during England's 1-0 loss to Denmark in the Nations League - just days after helping Gareth Southgate's team to victory against Belgium.
"When Harry is part of the England team that beats number-one ranked Belgium, that's just a normal day and then you get the headlines when you get the sending-off," said Solskjaer.
"That's just football for you. There's so many ups and downs that we have got to deal with it, individually and as a group.
"Harry's got great resilience. I know he'll bounce back. I'll know that he wants to play, he wants to just work his way out of the last couple of games that he's been criticised (for)."
The United boss said at his pre-match press conference that Maguire had picked up an injury against Denmark and would have a fitness test on Friday.
United head to Newcastle looking to react to the 6-1 humbling at home to Tottenham before the international break.
"It's one of those things that you have to get over as soon as you can and move on," Solskjaer said. "We know any little chance from outside... you want to create a division.
"I think Bruno (Fernandes) spoke really well the other day about how we are united, we have to stay together. We can't listen to everyone outside. We've got to just get on with it."
Solskjaer, speaking for the first time since the club brought in Edinson Cavani, Facundo Pellistri and Alex Telles on transfer deadline day, said he was looking forward to integrating the new players.
However, Cavani is yet to join the squad because he is in quarantine and will miss the trip to St. James' Park.
During the international break Paul Pogba once again sparked speculation about his Old Trafford future by saying it was a "dream" to play for Real Madrid one day but Solskjaer was relaxed about the situation.
"Paul's our player, he's going to be here for another two years and I'm sure Paul is focused on doing his best for us and we want to see the best of Paul," he said.
The United boss was also asked about "Project Big Picture", a radical plan to restructure English football backed by United and Liverpool, which was rejected by Premier League clubs this week.
Solskjaer said United had a responsibility to help clubs lower down the football pyramid, who were struggling during the coronavirus pandemic.
"For me, the fans - that's the key thing for me, that we want to get the fans back in the stadiums, which will help the other clubs," he said.
"I'm just very glad that we're looking into (it) and we're trying to help, and the talks have started."