In the summer of 2024, England international Gallagher made the biggest move of his career by joining Atletico Madrid for a fee worth up to £38 million ($51m). That ended nearly two decades at Chelsea, with the midfielder sending a heartfelt message to fans following his exit.
"To everyone at Chelsea Football Club and especially the fans, I want to say thank you for everything in the last 18 years.. You made my dreams come true and I'll forever be grateful. I want to wish you all the best for the future and I'll see you soon," he said.
"It's been an absolute honour every time I put on the shirt, and it was a dream come true to captain the team on many occasions. I loved every moment. These memories will last forever. I appreciate all the love and support from the fans. Hearing the chant of my name at the Bridge is a special feeling, and the banner you displayed meant the world to me. Thank you for everything. I wish the club all the best for the future, and I hope to see you all soon at Stamford Bridge!"