Nottingham Forest completed the signing of Ivory Coast centre back Ousmane Diomande from Sporting Lisbon on August 11, 2026. The 22-year-old defender joined Forest on a four-year contract with an option for an additional year [1, 2, 3, 4].
The transfer fee was undisclosed by the club, but British media reports estimate it between £34 million and £34.3 million [1, 2, 3, 4]. Diomande previously played for Danish side Midtjylland before moving to Sporting Lisbon in January 2023 [2, 3, 4].
During his time at Sporting, Diomande made 132 appearances in all competitions. He was instrumental in Sporting winning back-to-back Primeira Liga titles in the 2023-24 and 2024-25 seasons, as well as the 2024-25 Portuguese Cup [1, 2, 3, 4]. He also played a key role in Sporting’s run to the Champions League quarter-finals last season, starting both legs against Arsenal [4].
Internationally, Diomande represented Ivory Coast at the 2026 FIFA World Cup. He played the full match in their group stage win against Curaçao and featured as Ivory Coast exited in the round of 32 following defeat by Norway [1, 2, 3, 4].
Forest finished 16th in the Premier League last season and appointed Austrian Oliver Glasner as manager in July 2026 [2, 3]. George Syrianos, Nottingham Forest’s Chief Football Officer, praised Diomande as “a powerful, commanding defender” with a winning mentality who shares the club’s ambition for success. Syrianos added that Diomande’s experience in title-winning teams and the Champions League phase provides a strong foundation for him to integrate well at Forest [2, 3, 4].
Diomande expressed his excitement at joining the club, saying, “It is a historic club, and it motivates me to join such a club. I believe we can achieve very good things this season and I am looking forward to meeting the players and head coach. I will give my best” [1].
Nottingham Forest will begin their 2026-27 Premier League season at home against Leeds United on August 22, 2026 [2, 3].
