Keisuke Osako was born on 28 July 1999 in Kagoshima, Japan, and came through Sanfrecce Hiroshima's youth ranks. He has been a one-club player throughout his career — the senior goalkeeper of one of the J1 League's most-decorated sides.
His Sanfrecce career has been remarkable for consistency. Across 2024 and 2025 he played 38 J1 League matches in each season, plus 9 AFC Champions League Elite matches and Super Cup, J.League Cup and Emperor's Cup contributions. With Sanfrecce he won the J.League Cup in 2022, the Super Cup in 2025, and was a regular through Sanfrecce's continued continental campaigns.
For Japan, Osako was a member of the squads that won the EAFF E-1 Football Championship in 2022 and 2025. He played 1 EAFF E-1 match in the 2025 tournament.
A 186cm goalkeeper with elite shot-stopping range, calm distribution and the experience of multiple AFC Champions League campaigns, Osako is one of Sanfrecce's most loyal academy products. He is a strong candidate for the 2026 FIFA World Cup squad as a senior backup goalkeeper alongside Schmidt, Gonda, Pisano and Tani.