After winning the League Cup in 1997 and 2000 he made an £11 million move to Liverpool in 2000, which, at the time, was the record transfer fee paid by the club.

He moved to Birmingham City in 2004 and after their relegation from the Premier League signed for Wigan Athletic for a club record £5.5 million fee in 2006.

[9] Heskey was a keen footballer in his childhood and played for Ratby Groby Juniors, a local youth team in Leicester.

[11][12] Progressing through their youth system, he made his first-team debut at the age of 17 while still a first-year trainee in a Premier League match against Queens Park Rangers on 8 March 1995.

[13] He helped Leicester earn promotion back to the Premier League, starting in the 1996 First Division play-off final on 27 May as they beat Crystal Palace 2–1.

[21] During this season however, he forged an effective strike partnership with Tony Cottee, who benefited from Heskey's unselfish style of play,[21] which manager Martin O'Neill claimed kept the club in the Premier League.

[24] Heskey signed for Liverpool on 10 March 2000 in a long-anticipated £11 million move, which, at the time, set the record transfer fee paid by the Merseyside club.

[26] Heskey made his debut in an Premier League clash with Sunderland on 11 March 2000 and scored his first goal in a 3–0 victory over Coventry City on 1 April.

[34] He was linked with a £12 million move to Tottenham Hotspur in December 2002, but Houllier insisted he was a part of his long-term plans and he remained at Liverpool.

[35] The same year, Heskey made a six-figure donation to aid a consortium led by Gary Lineker in their bid to buy-out his former club, Leicester City, who were experiencing financial difficulties.

[43] He suffered an ankle injury during a pre-season friendly against CA Osasuna, which put his Premier League debut against Portsmouth in doubt.

[70] Heskey picked up a hamstring injury during a match against Bolton Wanderers in December 2008, which resulted in him missing an FA Cup third round tie against Tottenham Hotspur.

[82] Under Gérard Houllier, who previously managed Heskey at Liverpool, the striker enjoyed a successful start to the 2010–11 campaign including winning goals in the local derbies with Wolverhampton Wanderers and West Bromwich Albion.

On 7 May 2011, in Aston Villa's home match against Wigan, Heskey barged into referee Mike Jones and continued to argue with him because he did not award a free kick for an alleged elbow by Antolín Alcaraz.

Caretaker manager Gary McAllister chose to substitute him for Marc Albrighton at half-time, and Heskey was not allowed to remain at the stadium for the rest of the match.

[92][93] Having finished 2012–13 with 9 goals in 23 appearances and earning a nomination for the Jets' Player of the Year award, Heskey signed a new contract for the 2013–14 season in April 2013.

[100] Heskey joined Cheshire League One club Egerton in 2017 as a coach, alongside Jlloyd Samuel, Jim Cherneski and Dean Gorré.

[104] Leicester Women's manager, Jonathan Morgan, was sacked on 25 November 2021 after the team began the 2021–22 FA WSL season with eight successive losses, and Heskey took over the role on an interim basis.

[105] Five days later, it was announced that Lydia Bedford would succeed Morgan as manager, but Heskey was allowed to prepare for the team's upcoming League Cup tie against Manchester United.

[108] Heskey gained his first international recognition with the England national under-16 team, making his debut on 26 April 1994 as a substitute in 1–0 win over Portugal in their opening match at the 1994 UEFA European Under-16 Championship.

[109][111] Heskey made his debut for under-18s on 16 November 1995 when starting against Latvia in 1996 UEFA European Under-18 Championship qualification, scoring both goals in a 2–0 win in the second and 58th minutes.

[116] Making his final appearance on 29 March 2000 in a 3–0 victory over FR Yugoslavia in a 2000 UEFA European Under-21 Championship qualification play-off,[115] he finished his under-21 career with 17 caps, in which he scored six goals.

[121] Heskey was selected in the squad for the 2002 FIFA World Cup in South Korea and Japan,[122] and was used as a makeshift option to play in England's left-wing role in the match against Sweden, but did not perform well out of his regular position.

[125] He and teammate Ashley Cole received abuse from some Slovakia supporters when England played them in a Euro 2004 qualifier in October 2002,[126] which led to UEFA opening an investigation into the allegations.

[133] Heskey was recalled into the England squad for the 2006 FIFA World Cup qualifiers against Northern Ireland and Azerbaijan in 2005, after having been dropped following the match against Ukraine in August 2004.

[138] Heskey also started the next match against Russia, fighting off competition from Peter Crouch for a place in the team,[139] during which he created an assist for Owen's second goal.

[152] He started in a friendly against Spain in February 2009, which drew an angry reaction by Villa manager Martin O'Neill, who wanted to know why Capello played Heskey after suffering from an injury.

[161] Heskey played as a striker, being a mobile yet powerful targetman, gifted with pace, physical strength, and an ability to utilise his height to win aerial challenges; he was also an intelligent and hard working player,[123][162][163][164][165][166][167][168] known for his movement and athleticism.

[170] His main contributions to the team lied in the way he held the ball up with his back to goal and drew defenders out, leaving space behind him for another player to score.

[178] He impressed the England staff with his versatility, as he could also play down the left wing,[179] in addition to his usual role as an out–and–out striker;[177] he also drew praise from managers and teammates over his selfless team-play.