Unai Simón Mendibil was born on 11 June 1997 in Murguía, in the province of Álava in the Basque Country, Spain. He came through the celebrated Lezama academy of Athletic Club in Bilbao and made his senior debut for the first team in 2019, becoming the club's undisputed first-choice goalkeeper across the following seasons.
At Athletic Club he has been a cornerstone of one of Spanish football's most consistent sides, earning consistent La Liga plaudits for his footwork — which is among the best of any Spanish goalkeeper — his shot-stopping reflexes and his composure in high-pressure situations. He helped Athletic Club win the 2023-24 Copa del Rey alongside Dani Vivian, ending the club's long title drought, and has been integral to their consistent top-half La Liga finishes and European qualification across multiple seasons.
His 2024-25 season continued at the same high level, with Simón recognised as one of the two or three best goalkeepers in La Liga and as a world-class operator at the international level. His footwork and press-resistant distribution have become hallmarks of a style that fits perfectly into Spain's possession-based build-up play.
For Spain he debuted in 2019 and rapidly became the first-choice goalkeeper, displacing David de Gea from the position he had held for a decade. He was the starting goalkeeper as Spain won UEFA Euro 2020 (played in 2021), the 2020-21 UEFA Nations League, and UEFA Euro 2024 in Germany — making him part of one of the most successful periods in Spanish international history. He is the certain first choice for the 2026 World Cup.
Standing 1.90 m, Unai Simón is a left-footed goalkeeper whose sweeper-keeper instincts, reflexes and footwork have drawn comparisons to Manuel Neuer in terms of integration of the goalkeeper into the outfield build-up. He is considered by many analysts to be the best goalkeeper in La Liga and one of the top five in the world, representing the evolution of the Spanish goalkeeping school since Iker Casillas.