Chelsea captain Cesar Azpilicueta has ended a trophy-laden 11 years at the club and is expected to join Atletico Madrid.
The 33-year-old Spain defender won every available honour at Stamford Bridge, including two Premier League titles and the Champions League.
Azpilicueta had a year left on his Chelsea contract.
"It is difficult to express how I feel, it has been incredible," he said.
In a social media video posted by the club, a tearful Azpilicueta added: "I feel I gave everything. I love it.
"I think it would be pretty obvious to pick the highest moment of my career, when we won the Champions League in Porto.