Pohang Steelers In 1998, Lee joined a
K League club
Pohang Steelers and started his professional career instead of entering university. Lee was named the
Rookie of the Year after scoring eleven goals for Pohang in his first
K League season. He also helped Pohang win the
Asian Club Championship in that year. In January 2001, he was sent on loan to a
Bundesliga club
Werder Bremen, but he failed to settle in Bremen. He played only seven matches as a substitute during six months. He scored six goals during seven league matches in early 2006 when his performance was at its height. In April 2006, however, he tore the
cruciate ligaments in his knee while playing in a league match that forced him out for six months, and was unable to play in the
2006 FIFA World Cup.
Enlistment in Gwangju Sangmu In 1998, Lee's father offered a bribe to an employee of the
Military Manpower Administration in order to dodge Lee's military service. The conspiracy ended in smoke, and was revealed by the prosecutor's office in October 2001. Lee and his father were criticised for their conspiracy, but the court only ordered the monetary penalty of his father. Lee wasn't punished at all, and even got an opportunity to exempt from military service by participating in the 2002 Asian Games. On 24 February 2007, he made his debut, coming on as an 85th minute
substitute for
Yakubu in the 2–1 win against
Reading. On 29 August 2007, he scored his first goal against
Northampton Town in the
2007–08 Football League Cup. On 26 January 2008, he scored his second goal against
Mansfield Town in the
2007–08 FA Cup. However, he didn't score during 23 appearances in the Premier League and disappointed English fans. His contract expired at the end of the 2007–08 season and Middlesbrough decided not to extend his contract.
Jeonbuk Hyundai Motors Lee signed a contract with
Seongnam Ilhwa Chunma in 2008, but his difficult time was continued. He was transferred to
Jeonbuk Hyundai Motors in the 2009 transfer window. In the
2009 K League, Lee became the top scorer by scoring 21 goals during 29 appearances, and Jeonbuk won their first-ever league trophy. He was named the Most Valuable Player after spending a successful season. In the
2011 K League, Lee recorded 16 goals and 15 assists during 29 appearances, leading Jeonbuk's second league title. He became the Most Valuable Player once again as well as the
top assist provider. He also led Jeonbuk to the
2011 AFC Champions League Final after scoring nine goals until the semi-finals. Jeonbuk lost the final to
Al Sadd after penalty shoot-out, but he was named the Most Valuable Player and the top scorer. On 3 March 2012, Lee became the K League's all-time leading scorer with 117 goals when he got two goals in the
2012 season opener against Seongnam Ilhwa Chunma. In 2013, Lee was involved in a bizarre incident in a K League match against
Seongnam FC. While attempting to return the ball to Seongnam's goalkeeper after an injury stoppage, he accidentally struck it past him from 40 yards to level the score at 1–1. Jeonbuk goalkeeper
Choi Eun-sung then sportingly scored an
own goal on purpose to restore Seongnam's lead. Lee won his third and fourth MVP award after adding K League titles in 2014 and 2015. On 15 March 2016, Lee scored his 30th AFC Champions League goal against
Becamex Binh Duong and became the
AFC Champions League's all-time top scorer. On 26 November 2016, Lee and Jeonbuk won the
2016 AFC Champions League after defeating
Al Ain in the final. In the
2016 K League 1, Jeonbuk was deducted nine points for bribing two referees, and Korean fans protested that the punishment was too light. However, Lee ignored the corruption of his club, and didn't accept the result after losing the league title. On 2 June 2019, he scored his 200th career goal at
Jeonbuk Hyundai Motors in a match against
Sangju Sangmu. On 9 May 2020, Lee scored the only goal in a 1–0 win over
Suwon Samsung Bluewings, which was notable for being the first league match in the world during the
COVID-19 pandemic. On 1 November 2020, Lee played virtually last game of his 23-year playing career, and got his retirement ceremony immediately after the game. This game, finished as a 2–0 victory over Daegu FC, was the last round of the
2020 K League 1, and Jeonbuk sealed their fourth successive title. On 8 November 2020, he played his last match as a substitute for eight minutes in the
2020 Korean FA Cup final, and got his last trophy. ==International career==