Melbourne: Anna Meares of Australia kicked off the defence of her sprint crown at the World Track Cycling Championships on Thursday by setting a world record of 10.782sec for the 200 metre flying start.

Meares' time, set during qualifying for the first round of the women's sprint tournament, beat the previous mark of 10.793 set by Lithuania's Simona Krupeckaite in Moscow in May 2010.

"I was nowhere near expecting that," said Meares, the only rider from the 24 qualifiers to dip under the 11-second mark.

"I would have been really pleased with a low nine (10.9) high eight (10.8) which is right around a PB (personal best) mark for me. Anything in the eight (10.8) would have been perfect."

After catching a glimpse of her time on the scoreboard, Meares put her hands to her mouth in disbelief.

"I was surprised during the effort because I remember when I sat down I was thinking to myself 'this doesn't feel good. Go! Go! Go!, Go harder!" she added.

"I probably should do that every time I do a 200 because I ended up breaking the world record."

Although fast qualifying times are a good indicator of a rider's form, the sprint tournament is a notoriously difficult exercise in which tactics and timing play decisive roles over several gruelling rounds of duels.

"For me that's a new benchmark. It's a new level I've reached and I'm really proud of that but speed's only one part of this game," said Meares.

"It's down to tactics, it's down to nerves, it's down to decision-making and speed doesn't win it for you. I've got to get it right across the board if I want to come home with that world title."

However Meares, said to be on the form of her life, looks well-positioned to defend the maiden world sprint title she won in the Netherlands last year -- seven years after a runner-up place at the 2004 Melbourne worlds.

The Australian's 2011 feat brought an end to the domination of Britain's Victoria Pendleton, the Olympic champion from Beijing who had been gunning for a sixth world title in the event.

Meares, who finished runner-up to Pendleton in Beijing only months after a crash had left her in a wheelchair, also beat the Englishwoman at the London Olympic velodrome in February when the final leg of the World Cup was held as an Olympic test event.

Meares' world record was the fourth to be set at the Hisense Arena in two days.

On the opening day on Wednesday the German team sprint duo of Kristina Vogel and Miriam Welte twice beat the British-held world record of 32.754sec for the two-lap power event in 32.630, then 32.549.

Later on Wednesday the British men's pursuit team broke their own world record of 3min 53.314sec, set during the Beijing Olympics, on their way to beating Australia to gold in a time of 3:53.295.