The Spain international was influential for the club last season, as they finished third in the Premier League and claimed the UEFA Europa League title.

His form earned him a nomination for the Professional Footballers' Association Player of the Year Award.
But speculation has since mounted that newly-appointed Chelsea manager Jose Mourinho could look to offload the 25-year-old, in order to free up space in his squad for other targets.
Mata, however, has refuted such claims and says he is enjoying his spell at the London club.
"Nobody at Chelsea has told me that Mourinho wants me out," he told Marca.

"When I finished the season I was told that they were very happy with my performances and with the two years I've spent with the club.
"I have three years left on my contract. I'm very happy at Chelsea.
On Mourinho, Mata added: "I'd prefer to wait until I meet him and work with him before I judge him. That's simple logic."