Tsukasa Morishima was born on 25 April 1997 in Suzuka, Mie. He came through Sanfrecce Hiroshima's youth ranks and won the Super Cup in 2016 and the J.League Cup in 2022. In August 2023 he moved to Nagoya Grampus.
With Nagoya he won the J.League Cup in 2024. The 2023 split season produced 12 J1 matches with Nagoya and 20 J1 matches with Sanfrecce; 2024 brought 37 J1 matches with 3 goals and 4 assists; and 2025 produced 36 J1 League matches with a goal and 5 assists.
For Japan, Morishima won the EAFF E-1 Football Championship in 2022.
A 175cm two-footed central midfielder with vision, ball-control and the goal-scoring instinct of a creator who arrives in the box, Morishima is one of the J1 League's most reliable senior creative midfielders. He is a candidate for the wider 2026 FIFA World Cup squad as a J-League-based attacking midfielder option.