"I would like to tell you how I felt during this adventure. Things didn't start well at all," the Spain international wrote on social media.

"After a long time at home, changing everything wasn't easy."

Before moving to Stamford Bridge, Saul played 33 times during Atletico's title-winning campaign in 2020-21.

He made just 23 appearances in all competitions for Chelsea, starting only five games in the Premier League.

"Little by little things got better. Everything in life serves to improve and learn, and that's what I take from this adventure," Saul said.

"I'd like to thank the club for trying to take care of every detail to make me feel at home.

"But above all, I wanted to thank my team-mates. They have been fundamental so that I wouldn't fall apart. They helped me to continue supporting the team and live a calm and positive day to day."

The club said: "Chelsea would like to thank Saul for his efforts during the season and we wish him all the best for the future."