Early career Diouf started his career in France with
Sochaux-Montbéliard. He made his debut appearance in a 2–1 win against
Bastia on 12 November 1998, before moving to
Rennes for the 1999–2000 season. He moved to
Lens the following season, spending two years at the
Pas-de-Calais.
Liverpool In early June 2002 he was reportedly linked with the English club
Liverpool who had also just signed his club and international compatriot
Salif Diao. The news initially broke following his Man of The Match performance in the opening
FIFA World Cup 2002 1-0 group game vs France, who were the defending World and European Champions and one of the favourites to win the 2002 tournament. Lens initially denied that the signing had been made, but it was finally confirmed on 2 June with an estimated price tag of £10m. His continued impressive performances in the World Cup for Senegal, where they reached the quarter-finals, led to much excitement prior to his arrival in England. Diouf was the striker that manager
Gérard Houllier hoped would take the Premier League title from
Arsenal, after Liverpool had finished in second place the previous season. He started the
2003 Football League Cup Final as Liverpool defeated
Manchester United. Liverpool fans had to wait until March 2003 for Diouf's next goal for Liverpool. That occurred in a 2–0 win against
Bolton Wanderers, in a game where he scored once and provided the assist for the second. The next game saw Diouf play in a
UEFA Cup match against
Celtic at
Parkhead which finished 1–1. The game marked a watershed in his career when, in the 87th minute, he spat at a Celtic fan, causing crowd disturbances and Diouf to be interviewed by the
police. He received a two match ban and was fined two weeks wages with Liverpool making a donation of £60,000 to a
Glasgow charity of Celtic's choice. Diouf failed to score for the remainder of the 2002–03 season or at all in the 2003–04 season which saw him pick up 13
yellow and one
red card which came on 7 January 2004 when he was sent-off in a 1–0 away win against
Chelsea for fouling
Adrian Mutu. By then he had become unpopular due to both his attitude and his lack of goals.
Jamie Carragher later said of him "''He has one of the worst strike rates of any forward in Liverpool history. He's the only no. 9 ever to go through a whole season without scoring, in fact he's probably the only no. 9 of any club to do that. He was always the last one to get picked in training''."
Sunderland Diouf signed for
Sunderland on 28 July 2008, after Bolton agreed to a transfer fee of £2.63m. He signed a four-year contract at the
Stadium of Light after undergoing a medical. Diouf said that he was happy to join Sunderland. Then-manager
Roy Keane stated he was happy that Diouf had joined Sunderland saying: "El Hadji has always been the kind of player opposition teams and supporters hate. That's why we're delighted to now have him in our squad." He was given the number 18 shirt and scored his first goal for the club against
Fulham at
Craven Cottage on 11 March 2009 in a 2–1 win. During the summer transfer window, Blackburn manager Sam Allardyce revealed that Diouf was acquired for £1 million. Diouf scored his first home goal for Rovers at
Ewood Park in the club's 3–1 victory over
Wolverhampton Wanderers on 12 September 2009. On 2 January 2010, he was sent off in a 3–1 defeat to
Aston Villa in the third round of the
FA Cup. On 21 March 2010, Diouf scored the equalising goal against Chelsea in a 1–1 draw at Ewood Park which opened up the 2010 title race. He started the next two Premier League games against Birmingham and Burnley; he then made his fortieth appearance for the club at
Fratton Park playing against bottom-of-the-league side
Portsmouth in a 0–0 draw on 3 April. By the end of the 2009–10 season, he had made 27 appearances, scoring three goals. On 20 August 2011, Blackburn manager
Steve Kean confirmed that Diouf was not in his first-team plans, and that he expected him to leave before the end of the 2011–12 transfer window. On 31 August 2011, Blackburn terminated Diouf's contract by mutual consent. He had fallen out with manager Kean after returning late for pre-season training.
Loan to Rangers during his time with
Rangers. On the last day of the 2011 January transfer window, Diouf joined
Scottish Premier League champions
Rangers on loan until the end of the
2010–11 season. He made his debut on 2 February, coming on as a 20th-minute substitute for injured teammate
Lee McCulloch during a 1–0 win over
Hearts at
Ibrox. He made his first start for Rangers four days later in a 2–2 draw with
Celtic in the
Scottish Cup. Diouf scored his first goal for Rangers on 24 February in a 2–2 draw against
Sporting CP in the
Europa League, netting the opening goal of the game with a header in the 20th minute. He then scored his second goal for Rangers on 13 March in a Scottish Premier League match with
Kilmarnock, again scoring the first goal as Rangers won 2–1. In March 2011 Diouf was part of the Rangers team that won the
Scottish League Cup after a
2–1 win over rivals
Celtic. Diouf also collected an SPL winners medal as Rangers performed a comeback from two points behind Celtic to win the league by one point.
Doncaster Rovers In October 2011, Diouf was handed a trial by
West Ham United and their manager, Sam Allardyce, his manager at both Bolton Wanderers and Blackburn Rovers. On 28 October it was announced that Diouf would not be joining the club because of a lack of fitness and his bad reputation. Allardyce later confirmed that the depth of feeling amongst fans was taken into account in his decision not to sign the player. On 31 October 2011, Diouf signed for
Doncaster Rovers on a three-month contract. He scored his first two goals for Doncaster against
Ipswich at
Portman Road on 5 November 2011, earning Man of the Match honours and a 3–2 victory. He took the captain's armband in a goalless draw against
Watford but a training injury meant he was unable to play the following games. On 2 February 2012, Diouf signed a six-month deal with the view to an extra year. After Doncaster were relegated from The Championship, On 25 April 2012, Diouf was believed to have held talks with
Leeds United with a view to signing him at the end of his Doncaster contract.
Leeds United On 9 August 2012, Diouf joined
Leeds United on trial and started training with the first team. Diouf was confirmed to have signed a non-contract deal with Leeds United on 11 August. Diouf appeared as a substitute in the second half for Leeds against
Shrewsbury Town in the League Cup on 11 August. Diouf made his league début for Leeds as a first-half substitute in their 1–0 victory against
Wolverhampton Wanderers. He made his first start for Leeds in their 2–1 victory over
Peterborough United on 25 August. On 1 September, Diouf scored his first goal for Leeds in a 3–3 draw against his former club
Blackburn Rovers. After the match it was announced that Diouf had signed a permanent contract at Leeds until January 2013. Diouf was named captain against his old side
Bolton Wanderers in a 2–2 draw on 2 October. Diouf scored his fourth goal of the season on 30 October in a 3–0 League Cup win against Premier League side
Southampton F.C. to help Leeds advance to the quarter-finals of the competition. Diouf scored his milestone 5th goal of the season with a penalty to help earn Leeds a 2–2 draw against
Brighton on 2 November. On 14 December 2012, Diouf signed a new 18-month deal at the club taking him until the end of the 2013–14 season. He scored his 7th goal of the season against
Brighton on 27 April, but received his first red card as a Leeds player for celebrating it with a rude 'gesture' towards the Brighton fans. In May 2013, after Guinea club
AS Kaloum claimed to have signed Diouf, Leeds United and Diouf strenuously dismissed the claim as 'complete rubbish,' stating that Diouf would be playing for Leeds in the 2013–14 season. Diouf was ruled out of the entire 2013–14 pre-season due to a shin infection. On 15 August 2013, the
Yorkshire Evening Post reported that Diouf had been made available for transfer. In December 2013, it was revealed that Diouf had missed several Leeds fixtures and training sessions due to unspecified 'personal problems', and in order to attend the funerals of former mentor and
Senegal coach
Bruno Metsu and former
President of South Africa Nelson Mandela. Diouf made his first start for Leeds in several months on 28 January in a 1–1 draw against
Ipswich Town. It was to be his final game for the club. On 16 May 2014, Diouf was released.
Sabah FA In November 2014, Diouf signed a one-year contract with Malaysian side
Sabah FA of the
Malaysia Premier League, and was named team captain. However, Diouf soon found himself embroiled in controversy with his new club after comparing it unfavourably with rival club
Johor Darul Takzim II F.C. during an interview with Johor TV. Diouf was reported to have said that "he is willing to build a JDT academy on his own land in Senegal and JDT will get the monetary returns from the proceed of selling players to European countries. He also said that he is willing to play for JDT without any money because of his love for the state of
Johor as well as being impressed by the vision and mission of the club". Diouf said this was due to the lack of vision and mission by Sabah Football Association (SAFA). Deeming this behaviour "unprofessional," Sabah stripped Diouf of the captaincy in July 2015. ==International career==