The world's three fastest hurdlers safely advanced in the heats of the world championships on Sunday, but the best time was made by U.S. rising star Jason Richardson in 13.19 seconds.

China's Liu Xiang(L) competes during the heat of men's 110m hurdles at the IAAF World Championships in Daegu, South Korea, Aug. 28, 2011. Liu advanced to the next round with 13.20 seconds. [Xinhua]

China's Liu Xiang, the former world and Olympic champion of the men's 110m hurdles, was the fastest among the big three as he easily led heat one to finish in 13.20.

David Oliver, the world's leading athlete of the season, was in third place by 13.27 while world record holder and Olympic champion Dayron Robles was the only one among the three hot contenders who did not lead the group. The Cuban clocked 13.42 to cross the line just behind another U.S. runner Aries Merritt on 13.36.

Richardson beat teammate Oliver in the Diamond League Stockholm leg to win the gold medal and was the fourth fastest hurdler this year with a personal best of 13.08.

On the other hand, Ryan Brathwaite's defence of his world title came to a premature end when the 23-year-old from Barbados was run out in the heats.

Brathwaite, who enjoyed a dream run to take the gold medal in Berlin two years ago, finished fifth in the first heat in 13.57 and became the third world or Olympic champion in two days to make an early exit following the demise of Steve Hooker of men's pole vault and Christine Ohuruogu of women's 400m.

However, it was not a shock as Brathwaite came to Daegu with a personal season best of only 13.54.

The men's 110m hurdles is set to be the race of the Championships here in Daegu, featuring the three fastest men in history, who are Robles (12.87), Liu (12.88) and Oliver (12.89).

However, the final on Monday might be a fierce fight among four to five guys.

In seven Diamond League races up to and including London only Robles (three wins) has won more than once. Liu, Oliver, Merritt and Richardson have won once each.