Liverpool snapped up this Senegal star from Lens for £10million fee a few weeks after he had helped his country to a superb 1-0 victory over France in the opening game of the 2002 World Cup.
Senegal qualified for the finals largely thanks to two qualifying hat-tricks netted by Diouf, and would go on to make the last eight.
The striker, who moved to Lens via Dakar, Sochaux and Rennes, is a strong running player who earned the nickname 'Serial Killer' from his team-mates due to his impressive goalscoring tally.
Disciplinary problems dogged the early stages of Diouf's career at Rennes but he seems to have matured along with his success.
Diouf told the club's official website: 'I'm delighted to be joining Liverpool. Liverpool are a club that expects to be one of the best in Europe. I want to be one of the best players in the world and I'm sure that at Liverpool and with a great coach like Gerard Houllier I can do that.'
Liverpool had already agreed a deal with French club Sedan for fellow-Senegal midfielder Salif Diao. Diouf signed a five-year deal at Anfield.
Made his bow in the 1-0 FA Community Shield defeat at the hands of Arsenal.
Was immediately welcomed into the hearts of the Anfield fans as he scored twice on his home debut in a 3-0 win against Southampton.
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