Athens - John Capel, the 200-metre world champion in 2003, was removed from the US 4x100-metre relay lineup at the last minute because he had tested positive for marijuana earlier this month, a source close to the situation said on Saturday.
Capel had been scheduled to run in the relay semi-finals on Friday night, but US coach George Williams decided to pull the sprinter from the line-up when he learned of the test result, said the source, speaking on the condition of anonymity.
Shawn Crawford, this year's Olympic 200-metre champion, replaced Capel and the US team easily won their heat in 38.02 seconds.
Crawford said he didn't know why he was contacted about an hour before the race and told he would run.
A positive marijuana test results only in a warning, and Capel still was eligible to run in the relay. But Williams decided to pull him from the team anyway.
Capel tested positive on August 9 in Munich at the three-way team competition between the United States, France and Germany.
Any other positive test of a so-called "minor" drug will result in a two-year ban from competition.
Capel, 25, had been scheduled to run only in the semi-final, so being pulled from that race would cost him a gold medal if the heavily favoured Americans win on Saturday night.
He did not qualify for any individual races at the U.S. trials in June.
Capel's friend and training partner in Florida, Bernard Williams, tested positive for marijuana at a meet in Seville, Spain, on June 5 and is on probation.
Williams won the silver medal in a US sweep of the Olympic 200 on Thursday night.
Afterward, Williams said he had learned from his mistakes and was no longer using the drug.
Marijuana has caused serious trouble for Capel in the past.
A football wide receiver at Florida, he was drafted by the NFL's Chicago Bears in 2001, but tested positive for the drug at the draft combined.
Then on May 5 of that year, he was charged with possession of marijuana, and the Bears released him.
In 2002, he failed to make the roster for the Kansas City Chiefs and returned to running on the advice of coach Dick Vermeil.
Four years ago in Sydney, Capel was a favourite in the 200, but said he went out partying with friends the night before the finals.
He faltered out of the start in the race and finished last.
"I wasted a couple of years of my career, of my life," Capel told the Houston Chronicle just before the Athens Games began. "But I'm thankful that I was able to get back before it was too late."
