Cheick Diabate came to Exeter City as a sixteen-year-old trainee from London. After making his debut in the EFL Trophy at seventeen he firmly established himself in the second half of 2021/22 as City won promotion. 

Cheick, a defender, was on Stevenage’s books when he was at school before switching to City as a trainee in 2018. In 2019/20 Cheick had loans at Buckland Athletic and Tiverton Town before making his first-team debut against West Bromwich Albion under-21 in the EFL Trophy on 17 October 2020.

Cheick played in first-team friendlies in July 2021 before joining Southern League side Truro City on loan until January 2022. He was recalled before the Christmas fixtures and made his league debut at Sutton United on 1 January 2022. Then, after playing in the intervening fixtures, Cheick scored his first league goal at Walsall on 22 January 2022. By the end of the season, as Exeter won promotion, Cheick had played eighteen league games - all from New Year onwards. Cheick was duly named Exeter City Disabled Supporters Association Most Improved Player. 

Cheick signed a new two-year contract in June 2022 and continued to feature during 2022/23. Struggling to secure a place in City's defence during the first half of the following season, Cheick made several appearances as a striker ahead of a more-settled second half of the season which led to him signing a contract extension through to the end of 2024/25.