Rio Ferdinand remains "uncertain" about Matthijs de Ligt ahead of his reported £42.9million switch from Bayern Munich to Manchester United. 

De Ligt, who made 30 appearances in all competitions for Bayern last term, is set to reunite with Erik ten Hag at Old Trafford having played under the Dutchman at Ajax. 

United are after defensive reinforcements following the departures of Raphael Varane and Willy Kambwala, having just endured a campaign that saw them concede the most goals in a season in their Premier League history (58). 

However, Ferdinand, who made 312 appearances across a 12-year stint with the Red Devils, is unsure whether De Ligt's arrival will solve their issues. 

"I watched him at Ajax and he was brilliant in that year when Erik ten Hag was the manager, and they got to the semi-final [of the Champions League]," Ferdinand said on his YouTube channel.  

"He was brilliant, commanding, everything you want in a defender.

"He's had a lot of injuries, hasn't started many games over the last two or three years and Man United are spending £45-50million on him.

"Is he going to come into Man United and make a difference? I think it's a big ask for him and all eyes are going to be on him.

"Big pressure, big opportunity for him, but there's a lot of uncertainty I think with this signing because of his previous seasons with two big clubs (Juventus and Bayern Munich) not going as well as we'd have anticipated."

He then added: "I don't think he's the answer, but it's a great opportunity for him to go in there and go, 'You know what guys? I'm going to rectify my last couple of seasons.

"That's not the real me, and I'm going to show you."