Chelsea acquired Gittens from Borussia Dortmund for a total fee of £52 million, including the potential for additional payments.
Gittens previously played for Manchester City, where he was a trainee. He has also played for Dortmund since 2020, scoring 17 goals and providing 14 assists in 107 matches.
When asked about joining Chelsea, Gittens expressed his excitement, saying: "It feels great to join such a big club. I'm looking forward to learning from my teammates and pushing myself to improve."
