The 26-year-old signed for the Red Devils from Leicester City back in August as Ole Gunnar Solskjaer moved to strengthen his squad ahead of his first full campaign in charge.
Maguire has been a regular fixture in the Manchester United team this season and has started all four of the Red Devils’ opening Premier League games.
The central defender has been brought in to add some much-needed stability to the back line at Old Trafford as Solskjaer looks to try and steer the Red Devils back into the top four.
Maguire played the full 90 minutes as England coasted to a 4-0 win over Bulgaria in Euro 2020 qualifying on Saturday.
And Manchester United legend Keane seems to think that Maguire still has quite a lot of room for improvement.
Speaking to ITV Sport, Keane said: “I think he’s done OK.
“We were talking about how good he is on the ball, but defensively I still think he’s… I still have one or two question marks over him.
“I always worry about his pace on the turn.
“I remember the first goal against Crystal Palace where he’s not doing the basics, covering round his other centre-half.
“Listen, he’s 26 years of age now, you’re worried if you’re pointing these things out to him.”
Manchester United will return to Premier League action after the international break with a home clash against Leicester City at Old Trafford on Saturday.
The Red Devils have only won one of their opening four games in the Premier League this season.
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