He once was a humble cyclist with a reputation for grit, whether riding with broken bones so painful that he ground 11 of his teeth to nubs or crying openly during the 2004 Tour de France when his beloved dog and constant companion Tugboat had to be put down.
On Friday, Tyler Hamilton, 38, announced his retirement from cycling after failing a doping test for the second time in his career that included a dramatic stage win at the 2003 Tour de France and a gold medal at the 2004 Olympics.
Hamilton said that on Feb. 9 he took an over-the-counter medication for depression that contained a banned steroid. During a conference call Friday, Hamilton didn't deny failing the drug test. He raced in the Amgen Tour of California Feb. 14-22 and passed the drug tests conducted then, according to race officials.
When Hamilton rode alone and triumphantly on an 88-mile breakaway during Stage 16 of the 2003 Tour de France, with his shirt open and his broken right collarbone taped tight, up and down mountains from Pau to Bayonne, grimacing in pain and always looking behind him until there was no other cyclist in sight, he was the stage winner and suddenly famous in the United States.
He wasn't Lance Armstrong popular, but Hamilton began that race as a possible favorite until, in the very first stage he was caught in a crash and cracked that shoulder.
Instead of quitting, Hamilton gritted his teeth -- literally, he ground some of them down -- and finished the race fourth overall and with the reputation as a fierce fighter.
A year later Hamilton won his Olympic gold medal but six weeks after that he became a disgraced drug cheat after failing a blood doping test during the 2004 Spanish Vuelta.
Hamilton fought the charge but served a two-year suspension that ended in 2007. Last year Hamilton was signed by Rock Racing, a controversial team that has become home to several doping-associated athletes and is owned by Michael Ball, who was been outspoken in his feeling that cyclists face an autocratic system that does not treat accused dopers fairly.
For Hamilton, the stresses of his personal life may have played a key role. In the last two years alone, he was divorced from his wife and his mother battled breast cancer.
Hamilton, who has been living in Malibu while training, said he had been taking prescription medication for depression but had stopped because he felt it was hindering his work on the bike. But in February, he said the depression returned, prompting him to take a medication that contained dehydroepiandrosterone (DHEA).
