Liu Xiang, left, presents a traditional Chinese embroidery as a gift to Johnson, right. 2006-09-20. [sina.com]

"There are currently four athletes who are able to break through the 13-second barrier regularly and a few more are running close to the 13-second mark...it's remarkable," said Allen Johnson, 1996 Olympic gold medalist and four-time World Championship winner in the men's 110-meter hurdles.

Johnson, 35, will be locked in a battle of generations with local hero Liu Xiang, 12 years his junior, at the Shanghai Golden Grand Prix this weekend. "The elder hurdlers, like me and Dominique (Arnold) and Terrence (Trammel) carry on while the youngsters keep popping up, combining for the boom."

Both Arnold and Trammel had signed up for the annual one-day tournament on Saturday, only to call it quits yesterday, citing injury woes, leaving Johnson the sole hurdle to Liu's drive to defend his Grand Prix title.

Johnson beat Liu into second place at the Athens World Cup last weekend, bringing the Olympic champion's scorching run this summer to an end. Liu recovered strongly from a sprained ankle earlier this year and peaked at the Laussane Grand Prix in July when he improved the world record to 12.88 seconds. He shared the old benchmark of 12.91 with multiple world champion Colin Jackson of Britain.

"That was a huge relief," Liu said. "People kept asking me when I will come up with a new world record. Now I have got them off my back. If I were to rate my 2006 season, I would give myself 99 points out of 100."

But the hurdler played down talks of any exceptional results in the immediate future. "It's no surprise that any one of us can win any race with the level of competition so high at the moment," said Shanghai native Liu, referring to a group of elite hurdlers, including Frenchman and reigning World Championship winner Ladji Doucoure, Cuba's upcoming star Dayron Robles, plus the American trio of veterans Johnson, Arnold and Trammel.