This included three golds at the 1999 World Championships, a feat which had previously only been achieved by Carl Lewis and Michael Johnson and has since been equaled by three others.

His career was affected by several injuries from 2001 onwards, although he won the 100 meters bronze and silver in the sprint relay at the 2004 Summer Olympics.

Over his career, he made the third most sub-10-second runs (52) in the 100m, tied with Usain Bolt and only surpassed by Asafa Powell and Justin Gatlin.

Following his track career he has become an ambassador for the IAAF and a television personality, appearing on Identity, Blind Date, and Dancing with the Stars.

After watching the Olympic final from the stands, Greene made his way to Los Angeles to seek the coaching of John Smith.

At the 2004 Summer Olympics in Athens, Greene added to his medal tally with the bronze after finishing third in his attempt to defend his 100 m title to Justin Gatlin, and a silver as the anchor leg runner on the United States 4 × 100 m relay team, narrowly denied another Olympic Gold by the British team, who won by 0.01 seconds.

On February 4, 2008, Greene announced his retirement from track and field in Beijing, citing nagging injuries and a wish to see new individuals succeed in the sport.

Greene admitted meeting Heredia and making the payment but claimed it was common for him to pay for "stuff" for other members of his training group, and reiterated that he had never used banned drugs.

[5][6] Greene was a contestant on Season 7 of Dancing with the Stars, and was paired with two-time champion Cheryl Burke.

Greene also appeared on the American television series Blind Date where he was paired with a woman named Christie.

Greene was also the cover athlete for the multi-platform video game International Track & Field 2000, which was developed by Konami.