Salif Alassane Diao (born 10 February 1977) is a Senegalese former professional footballer who played as a defensive midfielder.

Diao moved from Senegal to France when he was seventeen and started his career at Monaco, with whom he helped with the Trophée des Champions and Division 1.

He also won a runner-up medal in the 2002 African Cup of Nations, where Senegal lost in extra time to Cameroon.

He was signed by former Liverpool manager Gérard Houllier from French club Sedan for £5 million (€7.5m) just before the 2002 World Cup in South Korea and Japan.

He helped Senegal reach the quarter-finals, most notably in scoring a memorable goal against Denmark in the first round, although he was subsequently red-carded.

[3] He was left out of Liverpool's squad for the victorious 2003 Football League Cup Final[4] despite playing often in the earlier rounds, including the semi-final first leg against Sheffield United.

[5] Diao was played in his correct position by Rafa Benítez, but several poor displays saw him displaced by Xabi Alonso, notably after a 4–2 win at Fulham.

Liverpool were 2–0 down when Diao was substituted; he had been at fault for one of the goals Fulham scored whilst attempting a bizarre back heel.

The arrival of Rafael Benítez and defensive midfielder Mohamed Sissoko signalled the end of his Liverpool career.

At the end of the season, Pompey manager Harry Redknapp decided not to take up the option to sign him permanently because of his injury-proneness.

It is thought that the revival of Stoke City during the 2006–07 season was in a large part due to Diao's hard-working performances.

[21][22] Diao has appeared 39 times for Senegal, scoring four goals in the process since 2000, including a strike against Denmark at the 2002 FIFA World Cup after a series of quick passes by his teammates to set him up.