Atlético Madrid has officially secured the signing of midfielder Conor Gallagher from Chelsea in a deal valued at approximately €40 million ($44m), the La Liga club announced on Wednesday.

The transfer faced uncertainty after Atlético’s attempt to send forward Samu Omorodion to Chelsea fell through.

Gallagher had spent five days in Madrid earlier this month, with Atlético confirming his presence at their Metropolitano Stadium as the final details of his signing were being worked out. However, he had to return to the UK after Omorodion’s transfer collapsed.

Following a week of negotiations, Chelsea reached an agreement to sign João Félix from Atlético, enabling Gallagher’s move to be finalized. The 24-year-old has signed a contract with Atlético until 2029.

Gallagher took to social media to bid a personal farewell to Chelsea.

He wrote: “To everyone at Chelsea, thank you for making my dreams come true. It was an absolute honor to wear the shirt, and captaining the team was a dream come true.

“I cherished every moment. These memories will stay with me forever. I deeply appreciate all the love and support from the fans. Hearing my name chanted at the Bridge was something special, and the banner you displayed meant everything 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!”

Sources told ESPN that the England international turned down a new contract offer from Chelsea, which included a two-year extension with an option for a third season and a significant pay increase.

Gallagher had earlier rejected a move to Aston Villa, while Tottenham had been closely monitoring his situation for several months.

Having progressed through Chelsea’s academy, Gallagher established himself in the first team following a successful loan spell at Crystal Palace during the 2021-22 season.

He featured in 136 Premier League games, scoring 18 goals and providing 13 assists.

Atlético Madrid showcased their summer signings, including Gallagher and eight new additions to the women’s team, at an event attended by thousands of fans at the Metropolitano on Wednesday.

Addressing the crowd, Gallagher said: “I don’t speak a lot of Spanish, but I’m very happy. Come on Atleti!”

Atlético have had an active summer in the transfer market, also bringing in defender Robin Le Normand and forwards Alexander Sorloth and Julián Álvarez.

This report includes contributions from ESPN’s James Olley, Rodrigo Faez, and Alex Kirkland.