Former Chelsea midfielder Emmanuel Petit says they must keep hold of Toni Rudiger.

Bayern Munich have been heavily linked with a move for the 28-year-old centre-back and reports in Germany on Wednesday suggested the Bundesliga champions have the financial muscle to double his current £5million-per-year wages. Rudiger's Chelsea deal expires in June.

Speaking to bookmakers.co.uk, Petit said: "'If he leaves, it would be a real pity for Chelsea," Petit said. "If I remember correctly before Tuchel came in he was on the bench and wasn't playing. Now he looks like one of the best defenders around.

"He could leave on a free and Chelsea would have to spend a minimum of £30m to find a new defender of his level, and there's never a guarantee a buy will work out.

"If he asks for two more years, just give him the money.

"This guy is a survivor. Since Tuchel has been the manager he's been one of the top defenders in world football.

"He reminds me of the crazy defenders I used to play with back in the day like Martin Keown.

"Those types of guys were always really tough on other players, and playing against them was both a physical and mental battle because they could make you feel bad on the pitch.

"I think Rudiger is similar, and it must be very tough to be on the pitch with him because you can disappear very quickly. He always plays the ball but he also plays the players and strikers know that and it can be intimidating.

"Sometimes he tries to destroy strikers, and I don't really like that side of his game. But for me, the priority of a defender is to scare strikers.

"People might not understand that but it's true, you have to scare them to try and stop them from scoring goals. For me, Rudiger is one of the hardest defenders in the world."