Brentford have completed the permanent signing of Senegal international El Hadji Malick Diouf from West Ham United for an undisclosed fee.
The 21-year-old has signed a five-year contract, with a club option for a further year.
Diouf arrives in west London having spent the 2025/26 season in the Premier League with West Ham, registering five assists in 32 top-flight appearances.
The left-back has also established himself at senior international level, representing Senegal at the 2025 Africa Cup of Nations and this summer's FIFA World Cup.
Brentford head coach Keith Andrews said: "We're really pleased that we were able to sign Malick.
"He's a player that fits our ideal age profile, with lots of room to still develop.
"I think he had a really good year at West Ham in his first season in English football, and some of the qualities and attributes he has as a full-back really add to an already impressive part of our team.
"I'm really keen to get to work with Malick."
Born in Dakar, Senegal, Diouf began his career with Galaxy Football Academy before joining Académie Mawade Wade.
He moved to Europe at the age of 18, signing for Norwegian side Tromsø in February 2023 following a successful trial. Diouf made 21 appearances in all competitions during his debut campaign, scoring three goals and helping the club finish third in the Eliteserien.
His performances earned him a move to Slavia Prague in January 2024, and he scored on his league debut against Karviná the following month.
Diouf established himself as a key player during the 2024/25 campaign, scoring seven goals and providing three assists in 27 league appearances as Slavia won the Czech First League title by 16 points. He also featured 12 times in European competition that season.
The defender joined West Ham United in July 2025 and made his Premier League debut against Sunderland the following month. He became a regular during his first season in England, featuring prominently from the left side of defence.
At international level, Diouf made his senior Senegal debut in an Africa Cup of Nations qualifier against Burundi in September 2024.
He played the full 90 minutes as Senegal became the first African nation to defeat England in June 2025, before featuring at the 2025 AFCON and the 2026 World Cup.