The Blues signed the Spain international in a £71m fee from La Liga side Athletic Bilbao on Thursday evening ahead of the 17:00 BST deadline in England.
Kepa’s transfer fee eclipsed the £67m sum that Liverpool FC spent on AS Roma’s Brazil number one Alisson Becker to make the Chelsea FC signing the world’s most expensive goalkeeper.
The 23-year-old holds that hefty title despite having made a mere 54 appearances for Bilbao since breaking into the first-team over the past two seasons.
Kepa will be tasked with replacing Belgium international Thibaut Courtois after the former Chelsea FC first-choice goalkeeper completed his long awaited move to Champions League holders Real Madrid.
Former Chelsea FC goalkeeper Schwarzer has concerns about Kepa following his lucrative switch to the FA Cup holders.
“It is a risk,” Schwarzer told Sky Sports.
“He hasn’t played outside Spain before. You look at De Gea. When he first came to England. He struggled with the robustness and the physicality of it. Kepa isn’t big. Can he cope?”
Kepa will be hoping to follow in the footsteps of current Spain number one David De Gea, who moved to Manchester United from Atletico Madrid in a £17m deal in 2011.
The Red Devils star has since established himself as the Premier League’s best goalkeeper despite a shaky start to life at the 20-time English champions.
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