'Alonso can be the best left-back in Europe'

Fresh from signing a new deal with the club, Chelsea manager Maurizio Sarri has challenged Marcos Alonso to improve his defending and become the best left-back in Europe. 

He signed a new five-year deal with the club, as Chelsea secured the former Bolton Wanderers left-back's long-term future. 

"I am very happy with him and for him," Sarri told the 'Daily Mail'.

"You know that I think he can be the best left-back in Europe.

"He needs to improve in the defensive phase. He was used to play in a five in the defensive line. Now he is playing in a four, he needs to improve. If he can do that, he will be the best in Europe."

Marcos Alonso also revealed his goal to improve and kick-on in the Premier League. "That was my dream, to become one of the best in my position. I know I can always improve and get better", Alonso said. 

"It has been a few months talking about the contract but my intention was always to stay here. I am where I want to be. I am very happy to have signed for five years."