Darrell Vienna has never been the sort to shirk from challenges. The 55-year-old, Southern California based trainer is a former rodeo rider, possesses psychology and law degrees, respectively, from UCLA and Loyola University in Los Angeles, is a successful essayist, poet and television screenplay writer, and has been conditioning racehorses for a quarter of a century.

Vienna's barn has been home for many stakes winners, and its inhabitants currently include Nuclear Debate, whom he purchased privately for an outfit called Herrick Racing earlier this year. Nuclear Debate's career resume features a pair if Group 1 grass sprint victories in Europe. He has recorded a handful of Group 2, Group 3 and Listed stakes triumphs as well.

But Nuclear Debate has also mixed in some dreadful performances, none of which have been more disappointing than his pair of ninth-place finishes in the first two runnings of the Hong Kong Sprint.

For this year's third running of the HK Sprint, the purse has been elevated to HK$8-million (making it the world's richest race at the 1000-metre distance) and the race's status has been raised to Group 2. And Nuclear Debate has been shipped in to give it another try, this time under Vienna's preparedness - - yet another challenge, being met head-on by a trainer well proven for the task.

A six-year-old, gelded son of Geiger Counter (whose own sire was the illustrious Mr. Prospector), Nuclear Debate comes from some of the best bloodlines of any sprinter around. The gelding's trainer of record was John Hammond, prior to his being shipped to the United States (and Vienna's care) in October of this year.

Handling swift sprinters has long been a Vienna forte. He has been the trainer of three former world record holders: Native Paster, who sped through six furlongs on the dirt in a time of 1:13 3/5 at Del Mar in September, 1988; Classy Women, who registered a 5 1/2-furlong grass victory in a time of 1:01 at Hollywood Park in July, 1991; and Finder's Fortune, who won at 7 1/2 furlongs on the dirt in a time of 1:26 4/5 at Hollywood in April, 1993.

Many racing enthusiasts believe Nuclear Debate has ample ability to join this trio. His record includes 38 starts, nine victories, eight second-place and five third-place finishes, and career earnings of US$817,346.

During his 2000 campaign, Nuclear Debate's exploits were heralded by a 1 1/4-length victory in the five-furlong Nunthorpe Stakes (G1) at England's York course. On September 8 of this year, Nuclear Debate was a three-length winner of England's six-furlong Haydock Park Sprint Cup (G1).

Why he has not done better in Hong Kong is a bewilderment. Many racing observers view Nuclear Debate as a "soft turf runner," unsuited to the firm footing of the Sha Tin course. In the inaugural HK Sprint in '99, Nuclear Debate tracked the leaders until one furlong remained, then simply surrendered his sword and finished 4 3/4 lengths to the rear of victorious Fairy King Prawn.

In the 2000 HK Sprint, Nuclear Debate was sent off as the 8/5 favourite in the field of 14. Never in the hunt, he trailed early and could do no more than pass tiring horses inside the furlong grounds, ultimately finishing five lengths to the rear of victorious Falvelon.

Nuclear Debate commenced this season finishing second, missing top money by a pug nose, in the Mahab Al Shimaal Stakes in Dubai on March 1. Since then, he has registered his 'Haydock Park triumph, finished a solid second in a second try at the 'Nunthorpe and third in the Temple Stakes (G2) at Sandown, a race in which he encountered traffic problems but missed top money by only a half-length.

Unfortunately, though, Nuclear Debate's other side has been in evidence this year, too. In his most recent start, his first for Vienna, Nuclear Debate finished a lackluster fifth in the 5 1/2-furlong Hollywood Turf Express Handicap (G3) on November 23.

Jimmy Fortune and Gerald Mosse (in that order) rode Nuclear Debate in his first two attempts at the HK Sprint. The US Hall of Famer, Gary Stevens, will be aboard this year. Stevens is up to the challenge, as is Vienna. We will see if the same can be said of Nuclear Debate at Sha Tin Racecourse this coming Sunday, December 16.