Antonio Rudiger struggles to play in a back-four formation.
The German defender is out of contract in the summer and will likely leave Stamford Bridge.
Tottenham, Liverpool, Real Madrid and Barcelona are favourties in signing the 29-year old defender who has been a pillar for Chelsea in the last two seasons.
Arsenal legend Paul Merson has raised doubts on Rudiger’s ability of playing in a back-four.
“He struggles in a four,” said Merson. “I watched him when Tottenham come to Stamford Bridge.
“He did what Newcastle didn’t do the week before, when Kane went into deep, he just went in with him and followed him everywhere.
“He can do that because they are playing three at the back. You go with two at the back, then you are in trouble. This is a problem. You play to your strengths. He’s had a good season.
“He has been fortunate. He has pulled the wool over the fans’ eyes in a way. He’s not signing for Chelsea and the fans love him. It’s only because he’s playing well.
“I think if you don’t play a three, then I don’t think it’s a good buy, in my opinion. Playing in a three he’s the best about. He’s like David Luiz. Exactly the same type of player.”