The central defender has been settling into life at Old Trafford after having signed for the Red Devils from Leicester City in the summer transfer window.
The 26-year-old has been a regular fixture in the Red Devils first team so far this season but Manchester United have struggled to find consistent form under Ole Gunnar Solskjaer.
And former Tottenham Hotspur manager Sherwood has not been particularly impressed by Maguire or Manchester United as a whole this season.
Speaking in an interview quoted by Metro, Sherwood said: “[Maguire has been] average.
“I don’t think he’s been great but I don’t think Man United have been great.
“I don’t think it’s about individuals at the back, it’s about partnerships and him and Lindelof haven’t been good enough.
“Sooner or later they’re going to have to work on that on that training field and get a partnership.
“All the best centre half partnerships are not always necessarily the two best players. It’s the two that can work together better.
“At the moment I think their understanding is not correct. They’re not covering around each other enough.”
Maguire was named as the man of the match in the 4-0 win over Chelsea FC on the opening weekend of the Premier League season.
Manchester United will now switch their attentions back to Europa League affairs and their home clash against Astana on Thursday night, before their trip to West Ham United in the Premier League next weekend.
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