Poor Dwain Chambers. There he was, prior to heading out to the World Indoor Championships, talking about having finally put his drugs-tainted past behind him. And there he was, after coasting to the fastest time in the 60m heats in the grand Aspire Dome here in the Qatari capital yesterday, being bombarded by questions about what is referred to in polite track and field circles as "performance enhancement".

Judging by the pained expression on the Londoner's face, it made precious little difference that the queries happened to relate to others who had fallen foul of the drugs testers: Ivory Williams, the American who would have gone into the championships ranked No 1 in the 60m had his challenge not gone to pot courtesy of a positive test for marijuana; and Callum Priestley, the promising young British hurdler who has a doping case to answer for the use of the banned drug clenbuterol.

"It's unfortunate," Chambers said of Williams, who was withdrawn from the United States team late on Wednesday night, "but I've just got to concentrate on the job I have here." The Belgrave Harrier was equally reluctant to talk about Priestley, who trains at the same north London base as him, the Lee Valley Athletics Centre. "I'm just here to concentrate on this job and to try to help motivate other athletes who are out to do a job," he said.

Not that Chambers needed to concentrate for very long on his work yesterday. It took him 6.59sec to get from gun to tape and he won with such ease, never needing to hit top gear, that only a false start seems likely to stop him when it comes to the business end of the semi-finals and final today.

It would be a first global crown for Chambers, whose British team-mate Harry Aikines-Aryeetey also made the qualifying cut yesterday, clocking 6.72sec for third place in his heat. It would also complete a tortuous journey from villain to hero for the 31-year-old – seven years on from his positive test for a cocktail of drugs and four years on from his comeback after serving a suspension. "I've just let the past go and that's enabled everything to be so much more relaxed for me this year," he said.

Additional motivation yesterday was provided by what Chambers called "a great speech" to the Great Britain squad by Jenny Meadows, the appointed captain of the 35-strong team. Meadows was also in action on the opening day, and the 28-year-old Wiganer was in sparkling form in the 800m heats, advancing to tomorrow's final as the fastest qualifier. Meadows is gaining in assurance with every race, having taken the step from long-time also-ran to bronze medal-winner at the outdoor World Championships in Berlin last summer. Assuming pole position from the start yesterday, she held off Russia's Mariya Savinova in the home stretch, finishing 0.56sec clear in 2min 00.39sec. Savinova, blessed with the speed of a 52.05sec 400m runner, remains a major threat to the British captain, while Anna Pierce of the United States was an impressive winner of the other heat, albeit in 2:03.05. Still, Meadows will go into the final with a realistic shot at the gold medal.

"It was nice to run a half-decent time," she reflected. "Hopefully it will set me up for the final. Savinova is a great athlete and Pierce looked very good. I know her race was slow but the way she ran it was very good. You can never write off anybody in a final, but I have to keep telling myself, 'You're in the mix, Jen,' as well."