Justin Gatlin plays down Usain Bolt rivalry as stars qualify in Beijing

Justin Gatlin played down his rivalry with Usain Bolt after the world's leading 100 metre runners cruised into the World Championships semi-finals in Beijing.

American Gatlin, who boasts the four quickest times in the world this year, has largely been cast as the villain of the piece in the sprint showdown on account of serving two suspensions during his career for doping offences.

On the track, Saturday marked another impressive outing for Gatlin, who was the fastest qualifier with a time of 9.83 seconds in the sixth heat - albeit with the help of a 2.1m/s following wind.

The 33-year-old, who completed the 100m and 200m sprint double at the 2005 World Championships in Helsinki, declined to stoke the fires of any rivalry and told BBC Sport that it will be an "honour" to contest Bolt's title.

"I've worked really hard for this," he said. "It's not about me, it's about track and field, it's about the 100m, to come out here and make one of the most exciting races with Usain Bolt - it's an honour."

Bolt clocked a comparatively pedestrian 9.96 seconds in winning his heat, underlining the Jamaican's unfamiliar status as the underdog after an injury-hit season.

The 28-year-old ambled out of the blocks before working through the field courtesy of his familiar loping stride and felt he over-thought his work out of the blocks.

"I was thinking about the start too much," Bolt told BBC Sport. "Overall it was okay.

"I didn't use too much stress. I'm trying to get business done, that's all."