As 12 superstar riders congregate from all corners of the world, ready for battle in four legs of the Longines International Jockeys' Championship at Happy Valley, South African Gavin Lerena - taking his first rides at the iconic urban course - can cause a minor upset and hoist the trophy in tonight's Jockey Challenge.

Last year's champion jockey in South Africa, Lerena ($9) is aiming to follow in the footsteps of other riders from the country - most notably three-time winner and tonight's rival Douglas Whyte - to succeed in the rough-and-tumble environment that is Hong Kong.

The 30-year-old has one of the stronger books across the board and a number of honest rides, crucial in a competition like this.

His first ride, John Moore's Happy Moments, was pigeonholed as a dirt horse after a win on the surface in January, but he has been plain in eight starts on the all-weather track since. A switch to Happy Valley looks suitable and he could find himself in the placings.

Consistent types Noble De Man and Mr Right follow, before Superoi provides him with his best winning chance in the final leg.

For the danger, look to a Sha Tin-based rider in Brett Prebble.

Prebble opened up favourite in betting but had drifted to a $5.50 third favourite last night behind local champion Joao Moreira and Australian visitor Hugh Bowman.

For Prebble, the Melbourne boy who has called Hong Kong home for more than a decade, his fate will be known early - Dennis Yip Chor-hong's One Of A Kind looks on the verge of turning his form around and is a good each-way chance in the first leg, while Tony Millard-trained Strathearn looms as possibly the best bet of the four Challenge legs in the second.

If Prebble is not on the board after race five, he may find it tough, although Jolly Posh is well-drawn and should get the run of the race while Ruby Coast has been game in recent starts.

Other chances at odds are Maxime Guyon, whose best point-scoring chance is St Yazin for Gary Ng Ting-keung in race seven, and Keita Tosaki, who has a strong ride in the first leg in First Sight Love and could find himself in the placings on his other three mounts.