He came through the youth ranks at the Basque club following his move to the club’s youth academy Lezama in 2004.
Arrizabalaga made his professional debut during his loan spell at SD Ponferradina, starting a 1-1 draw with Racing De Santander.
Kepa gained more first-team experience during a loan stint at Real Vallodid in the Segunda Division in the 2015-16 season.
His Athletic Bilbao debut came in a 1-1 draw with Deportivo La Coruna in La Liga in September 2016.
Kepa earned his first Spanish senior cap in a 3-0 win over Costa Rica in a friendly in November 2017.
• Date of birth: 3 October 1994
• Age: 24 years old
• Place of birth: Ondarroa, Spain
• Nationality: Spanish
• Height: 189cm / 6ft 2ins
• Weight: 85kg / 188 lbs
• Transfer value: £71 million
• Wages: N/A
Kepa was born in Ondarroa, Biscay, Basque Country.
It wasn’t long before the promising goalkeeper joined Athletic Bilbao’s youth set up.
He got some experience representing CD Basconia in the Tercara Division in 2011.
Arrizabalaga earned a call up to the senior squad on 5 May 2012.
Kepa was on the bench but remained unused in a 0-0 draw against Basque rivals Real Sociedad in La Liga at the San Memes Stadium.
He was involved in Athletic Bilbao’s pre-season campaign before Kepa was on the bench for the Basque team’s 0-0 draw with Malaga at the start of the 2012-13 season.
Kepa was promoted to Athletic Bilbao’s Reserves team to cover Jon Ander Serantes.
The promising shot stopper made his debut for Athletic Bilbao’s second string.
He made his debut in a 1-0 win over UD Logroñés for the Segunda División B championship on 16 February 2013.
Arrizabalaga earned his first red card in a 3–1 home win over SD Amorebieta at the start of March.
Kepa suffered an injury to rule him out for the final months of the 2012-13 season.
The Spanish shot stopper was a substitute in Athletic Bilbao’s 2-2 draw with Elche on 31 October 2013.
Kepa moved to Segunda División side SD Ponferradina in January 2015.
He made his debut for SD Ponferradina in a 1-1 draw with Racing de Santander on 11 January 2015.
Arrizabalaga made 20 appearances in Spain’s second tier during his loan stint at SD Ponferradina. He helped Ponferradina win seven victories, five stalemates and eight losses.
Kepa was presented with the chance to get further first-team experience under his belt in the Segunda Division following a loan switch to Real Vallodid in 2015-16.
He made his first appearance for Real Vallodid in a 1-0 loss to Cordoba on 21 August.
Kepa was a regular for Real Vallodid throughout his loan spell at the Segunda Division outfit.
Arrizabalaga helped Real Vallodid to win 11 games, draw 15 times and suffer 14 defeats.
He sat on the bench for Athletic Bilbao’s 1-0 loss to La Liga giants FC Barcelona in the Spanish top flight.
Kepa made his Athletic Bilbao debut in a 1-0 win over Deportivo La Coruna on 11 September 2016. He made three saves to help the Basque side to secure three points.
He was unbeaten in his first six starts for Athletic Bilbao thanks in part to his 11 saves before Athletic Bilbao lost 3-1 to Las Palmas on 28 November 2016.
Arrizabalaga caught the eye with four saves to help Athletic Bilbao secure a 2-0 win against Real Sociedad in the Basque derby on 12 March 2017. Kepa topped that performance with five stops in a 2-1 win over Osasuna on 1 April 2017.
Kepa made 40 saves in his first senior season in 23 appearances in the 2016-17 La Liga campaign.
He was named in the starting line up for Athletic Bilbao’s 0-0 draw with Getafe in their opening La Liga fixture of the 2017-18 season.
Arrizabalaga made five stops to help the Basque side ease to a slender 1-0 victory over Eibar.
Kepa made seven saves in a 2-1 loss to Atletico Madrid on 20 September 2017.
He managed to keep a clean sheet in Athletic Bilbao’s goalless draw with Real Madrid on 2 December 2017.
Arrizabalaga made seven saves in a 2-0 loss to Spanish champions FC Barcelona on 18 March 2018.
His best performance of the 2017-18 La Liga season came in a 1-1 draw with Champions League winners Real Madrid at The Bernabeu. Kepa made nine stops in the Spanish capital.
Kepa finished the campaign with 99 saves in 30 La Liga games in the current campaign.
Kepa turned down the chance to move to Champions League holders Real Madrid in 2018.
Explaining the decision, Kepa said: “Rejecting Madrid? It’s true that during the process, I decided to stay on the fringes. It was a time when I needed to think things through.
“It was a life decision, deciding which path to take in my career. I needed time to get together with my family and closest friends.
“In the end, I wanted to be sure and weigh everything up. Once it became clear, I made the decision I made by signing a contract for several years.”
Kepa was linked with a move to Chelsea FC during the 2018 summer transfer window.
On 7 August, the Blues were reported to have activated Kepa’s £71.5m contract release clause.
Kepa was called up to Spain’s Under-19 team for the European Under-19 championship in 2012.
He impressed as la Roja made it to the European Under-19 championship final, including some heroics in a penalty shootout win over France in the semi-final.
The Athletic Bilbao goalkeeper helped Spain to beat England in the final to win the tournament.
He earned a call up to Spain’s Under-21 team in November 2013. Kepa made 22 appearances for la Roja’s Under-21 outfit.
Arrizabalaga was named in Spain’s senior squad for the first time as a replacement for Pepe Reina ahead of their 2018 World Cup qualifiers against Israel and a friendly clash against France.
However, Kepa didn’t make his first appearance for Spain’s senior team until a 5-0 win over Costa Rica in Malaga.
He was named in Spain’s 23-man squad for the 2018 World Cup in Russia but Kepa didn’t make an appearance.
• Kepa played under Leeds United manager Marcelo Biesla at Athletic Bilbao.
• However, it was under current FC Barcelona boss Ernesto Valverde that Kepa established himself as Athletic Bilbao’s first-choice goalkeeper.
• Kepa is smaller than current Chelsea FC number one Thibaut Courtois, who is four inches taller than the Athletic Bilbao star.
MORE: Christian Pulisic
MORE: The latest football news
MORE: The latest tennis news
BIOGRAPHY: Daniel Sturridge
BIOGRAPHY: Kepa Arrizabalaga