The Whitneys and the Vanderbilts have thrown fancier soirees during the Saratoga season (which ended today), but for a hard-core horseplayer nothing could have been more engaging than Harvey Pack's "Toughest Beat Party" the other night.

Pack, the host of a cable-TV racing show in New York, invited his guests to go before a camera and microphone and relate the circumstances of their toughest beat--their most heart-rending setback at a racetrack.

One horseplayer told about the day he couldn't get any money to bet a 22-to-1 shot he loved because the horse happened to be running on the day the great New York City blackout forced all the banks to close. Others told wrenching sagas of photo finishes and unjust disqualifications. But none was quite so exotic as the hard-luck story of Richard Valeriani, the NBC correspondent.

In 1963, after the assassination of President Trujillo, Valeriani was sent to the Dominican Republic to cover the election campaign between Juan Bosch and Viriato Fiallo. Naturally, he tried to enliven the assignment with an occasional trip to the racetrack in Santo Domingo.

Valeriani was sitting in the Hotel El Embajador, studying the entries, when he saw one respectable pedigree among all these rock-bottom animals. An entrant in the second race had been sired by the good American stallion Ambiorix.

"All the bellhops and the busboys and the waiters at the hotel were horseplayers," Valeriani recalled, "and when I asked them about the horse, they all said he was a dog -- he couldn't possibly win."

Valeriani was undeterred. When he got to the track, he used the horse in a gimmick resembling the modern Pick Six -- the objective being to pick every winner on the card. After one of his choices won the first race, he watched the despised son of Ambiorix win the second race at odds of 99 to 1.

Not many other patrons shared Valeriani's euphoria. "People jumped over the fence and blocked the track, yelling that the race had been fixed," the correspondent said. "They set fire to trash cans. Then an announcement was made that if the rioting didn't end, the rest of the races would be canceled and the Pick Six pool would go to anybody who picked the winners of the first two races. Now there was more booing and the crowd started stoning the stewards' box."

When racing was canceled, Valeriani said, "I felt terrific." And for good reason. His friends at the hotel told him that evening that there was probably $10,000 to $15,000 in the Pick Six pool. But one of the locals also informed him that the Jockey Club was going to hold a special meeting to approve the stewards' decision.

The meeting was held on the day before the presidential election. Valeriani had to go with a camera crew to the public square in Santo Domingo, and there he knew he would be able to learn the results at a nearby off-track betting shop. When he arrived, Valeriani found he wasn't the only excited person in the vicinity. Bosch forces were assembled on one side of the square, Fiallo forces on the other. Suddenly they started firing at each other. With bullets flying in all directions, Valieriani and his NBC colleagues hit the ground and lay there motionless.

They did, at least, until Valeriani excused himself and crawled in the direction of the OTB shop. When he got the news, he felt like inciting a riot. "They told me that the Jockey Club had reversed the decision of the stewards," he said. "There would be no payout on the Pick Six. Instead, the whole card would be rerun the following week. I was wiped out.

"Of course," Valieriani added, "I went back the next week. And, of course, this time my horse ran like a 99-to-1 shot."