United are also suffering in the Premier League as the 1-0 defeat at home to Crystal Palace on Saturday was their fourth so far this season.
Ten Hag’s men are looking to get back on track in the Champions League on Tuesday evening as they host Galatasaray at Old Trafford.
And Varane is confident that United have the squad that is capable of winning the competition.
‘I think that competition it’s about details, you have to be efficient to win that competition,’ said Varane.
‘I think what we can improve is to be more efficient in front of goal.
‘We have a very low number of occasions where we concede goals, we have to create a lot to score, so that’s the reality of the top level, you have to be efficient to win big trophies.
‘I think we have the quality in the squad to win the competition, but we have to improve and tomorrow [against Galatasaray] it’s a great opportunity to get the first points in the competition, to move forward and improve.’
When asked if he believes United are capable of winning the Champions League, Varane replied: ‘Yes, I think so. The quality is in the squad, as I said, this competition is difficult, you have to take care of every detail.
‘But we have a team with quality, with a good mentality, yes, we have to make some improvements it’s not the start of the season we expected.
‘But I still believe we have the quality to compete with the best teams in the world.’
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