2000 With the help of Coach Hee June Choi, Lee made a splash at the
US Open tournament, reaching the fourth round before losing to
Pete Sampras. En route to his fourth-round appearance against Sampras, Lee defeated
Jeff Tarango, 13th seed
Franco Squillari, and future
Australian Open runner-up
Rainer Schüttler.
2003 In 2003, Lee became the first Korean to win
ATP Tour singles and doubles titles by winning the singles tournament at the
Sydney International as a qualifier (beating
Juan Carlos Ferrero in the final) and the doubles tournament at the
Siebel Open in San Jose, California (partnering with Belarusian
Vladimir Voltchkov). At
Wimbledon, he was defeated in the first round by eventual champion
Roger Federer in straight sets.
2006 In the second round at
Wimbledon, Lee was defeated by former champion and two-time semifinalist
Lleyton Hewitt in five sets, including three tie-breakers. Lee had set points in the third set tie-breaker, but went on to lose the set after an incorrect line call. As Lee went on to win the fourth set the call probably prevented him winning the match against the eventual quarterfinalist.
2007 Lee matched his best Grand Slam performance by making the fourth round of the
US Open tournament. In the first round, he was forced to five sets before defeating
Dominik Hrbatý. Lee was pit against
Guillermo Cañas, who was the fourteenth seed in the tournament, in the second round. He defeated Cañas in three sets, setting up a third round showdown against nineteenth seed
Andy Murray. Lee got out to a quick two set advantage against Murray, eventually winning in four sets. In the fourth round, Lee played fourth seed
Nikolay Davydenko, who defeated the Korean in three sets. His fourth round showing at the US Open capped a very successful hardcourt series. During the
US Open Series, Lee reached the semifinals at the
Countrywide Classic in Los Angeles, the quarterfinals at the
Indianapolis Tennis Championships and at the
Legg Mason Tennis Classic. Lee set personal bests in a handful of categories, including match wins and money earned. He won a career-high 25 matches and earned $386,230. Overall, Lee compiled records of 16–15 on hard, 5–5 on clay, 3–3 on grass and 1–0 on carpet. In August, he achieved his career best ranking in singles as world No. 36 with the help of his coach, Hee June Choi.
2008 In the 2008 season, Lee had a disappointing losing streak and eventually fell out of the top 100. He did, however, match his best Masters Series result by making the fourth round of
Indian Wells, beating
Michaël Llodra,
Jarkko Nieminen and No. 5 seed
David Ferrer along the way.
2009 In 2009, Lee played one final time for Korea, in the Davis Cup play-off between Korea and China. He announced his retirement from pro tennis after the Davis Cup match, with Korea triumphing 3–2.
Doubles Lee sometimes played doubles alongside Korean-American player
Kevin Kim. The pair reached the third round of the
2005 French Open. ==Playing style==