Southampton have agreed to sign Rennes winger Kamaldeen Sulemana for a club record £22m, rising to £24.6m, according to BBC Radio Solent.
The Ghana international, 20, who primarily plays on the left, had also been linked with a move to Saints' relegation rivals Everton.
He is now having a medical in France before moving to Southampton.
The fee exceeds the £20m Saints paid to sign forward Danny Ings from Liverpool in 2019.
Sulemana joined Rennes from Danish club Nordsjaelland in 2021 and has played 20 times this season, scoring once and providing two assists.
He has won 15 caps for Ghana, including three appearances at the World Cup in Qatar.