Varane joined the club on a four-year-deal on Saturday after spending 10 years at Spanish giants Real Madrid and will wear the number 19 shirt at Old Trafford.
He is United’s third summer signing after bringing in former Borussia Dortmund winger Jadon Sancho and backup goalkeeper Tom Heaton from Aston Villa earlier in the window.
The 28-year-old was unveiled in front of the Old Trafford crowd ahead of the club’s opening Premier League game of the season at home to Leeds on Saturday, but was unable to feature after being registered too late.
Despite the signings of Jack Grealish by Manchester City and Romelu Lukaku at Chelsea this summer, Merson believes that Varane is the best deal of the window so far.
‘Raphael Varane will turn Manchester United into title contenders – he’s the signing of the summer in the Premier League. I think it’s as tight as it’s ever been this season and there’s four teams who could win the league,’ Merson told the Daily Star.
‘United weren’t one of them but Varane changes that. I think that’s a major signing. With all the class and experience he brings with him from Real Madrid, I think he’s going to have a massive impact.’
The French World Cup winner is expected to slot in alongside England’s Harry Maguire at the heart of the defence at Old Trafford, adding some much needed experience to their back line.
‘United now have a new Vidic and Ferdinand partnership to rely on at the back. Maguire can get tight to people and Varane can sweep up behind with his pace,’ Merson said.
‘United played with two holding midfield players a lot last season because Ole Gunnar Solskjaer didn’t trust his defenders. They won’t need to do that now. They were as good a counter-attacking team as anyone last season.
‘But now, with Varane, they can take more risks and play on the halfway line. That’s important against the lesser teams. You can really put them under pressure instead of having that fear of one long ball over the top catching you out.’
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