LONDON (AP) – British sprinter Dwain Chambers was suspended Tuesday for two years and banned for life from the Olympics, the first athlete punished for testing positive for the designer steroid THG.

THG, which was undetectable until last year, is at the center of the scandal surrounding a San Francisco-area lab accused of supplying dozens of professional athletes with banned substances. Chambers’ coach, Barry Bonds’ personal trainer and two others were indicted this month.

Chambers, the European 100-meter champion, tested positive in an out-of-competition drug test in August. UK Athletics suspended him, and under British Olympic Association rules, he is barred from ever competing in the Olympics.

“It’s an exceptionally sad day for Dwain and an exceptionally painful day for the sport,” UK Athletics chief executive David Moorcroft said. “But it is absolutely a price worth paying.”

Chambers, who finished fourth in the 100 at the 2000 Sydney Games, had been considered a potential gold medal contender at the Athens Olympics in August. His suspension will end Nov. 7, 2005.

“I think two years is pretty emphatic. It’s basically the end of a career,” said Nick Davies, spokesman for the International Association of Athletics Federations.

The 25-year-old sprinter has maintained he never knowingly took a banned substance and blamed his positive THG test on nutritional supplements.

The four other track and field competitors who tested positive for THG, or tetrahydrogestrinone, were Americans: shot putter Kevin Toth, 1,500-meter runner Regina Jacobs and hammer throwers Melissa Price and John McEwen. Their hearings haven’t been held yet.

Chambers’ California-based coach, Remi Korchemny, was one of four men indicted Feb. 12 on federal charges of supplying THG and other banned drugs to dozens of athletes.

The UK Athletics panel concluded that THG was “chemically and pharmacologically related” to the banned steroid gestrinone. It also said it had no evidence to prove Chambers intentionally took the banned drug.

“This is a test case for THG generally, and we were at the forefront of a worldwide issue,” Moorcroft said. “I’m relieved the verdict has been reached. I believe it is the right verdict.”

Under international rules of strict liability, athletes are responsible for any banned substances found in their bodies regardless of the circumstances.

Chambers’ lawyer, Graham Shear, said the sprinter continued to assert he never knowingly took a performance-enhancing substance. He said an appeal was being considered.

“Dwain has been given the minimum ban available in the circumstances and he continues to assert his innocence,” Shear said in a statement.

Shear said the tribunal noted there was “no clinical evidence” of a performance-enhancing effect of THG in the human body.

Chambers has 60 days to appeal to the international Court of Arbitration for Sport in Lausanne, Switzerland.

The ban was widely applauded by international sports and doping bodies.

International Olympic Committee spokeswoman Giselle Davies said the ban “serves as a warning to athletes that the world of sport takes the fight against doping very seriously.”

Dick Pound, head of the World Anti-Doping Agency, said the case shows that “those who cheat will be caught and will face the consequences.”

U.S. Anti-Doping Agency chief executive Terry Madden said he looked forward to THG hearings in the American cases.

Chambers, who has a best 100 time of 9.87 seconds, is considering a switch to American football as a wide receiver. He recently had a private tryout in London and was scheduled to fly to Miami this week for an NFL Europe training camp.

Chambers’ sample was analyzed at the Olympic doping control laboratory at UCLA, where scientists unmasked and developed a test for THG last summer.

The breakthrough came after an anonymous track coach sent a syringe containing the substance to U.S. anti-doping authorities.

Indicted along with Chambers’ coach were Victor Conte, founder of the Bay Area Laboratory Co-Operative in California; James Valente, vice president of BALCO, and Greg Anderson, Bonds’ trainer. The four pleaded innocent last week.

Chambers has said BALCO provided him with nutritional supplements, and that Conte assured him that all the supplements were within international rules.

Conte has denied being the source of THG.