Arsenal have signed Thomas Partey from Atletico Madrid on Deadline Day after meeting his £45m release clause.
Partey signed a long-term deal at the Emirates after he completed his medical and paperwork just before Monday’s 11pm deadline.
He will wear the No 18 shirt and will join up with his new team-mates next week after he returns from international duty with Ghana.
Partey has been a key player in Diego Simeone’s midfield since breaking into the first team from Atletico’s academy in 2015.
Mikel Arteta said: “We have been watching Thomas for a while, so we’re now delighted to add such a high quality player to our squad.
“He is a dynamic midfielder with great energy. He brings a lot of experience from a top club that has competed at the highest level in La Liga and the Champions League for several years.
“We’re very impressed with his attitude and his approach to the game. He’s an intelligent footballer and we’re looking forward to him integrating into our system and contributing to the progress we’re building at the moment at the club.”
Partey becomes Arsenal’s seventh signing of the summer, with the club having already signed Willian on a free transfer from Chelsea and defender Gabriel from Lille for £27m.