SARATOGA SPRINGS, N.Y., AUG. 23 -- The best sprinters in America haven't been able to beat Groovy this year. And neither has Bruce Lombardi.

Lombardi, the racing secretary at the New York tracks, gave the ace sprinter a 132-pound weight assignment for today's Forego Handicap -- one of the heaviest imposts for a major race in recent years.

But Groovy made light work of the task, leading all the way to win by 1 3/4 lengths over Purple Mountain. He sped the seven furlongs in 1:21 4/5.

Although sprinters rarely become stars, Groovy is arguably the most impressive racehorse of 1987. He had run four times before today, winning them all, easily defeating the best sprinters in the East, running six furlongs as fast as 1:07 4/5. His credentials were so formidable that three brothers from Texas -- Jack, Art and R.J. Preston, who are in the oil and gas business -- purchased him for $2 million, big money for a colt who tires beyond seven furlongs.

They left the colt in the care of trainer Jose Martin, who has managed Groovy flawlessly this year by letting him concentrate on sprinting. But Martin was genuinely concerned before the Forego. The 132-pound assignment, he said, "was an honor I could do without."

But Groovy never gave Martin, or those in the crowd of 33,346 who made him a 3-to-5 favorite, a moment's cause for concern. He broke with his customary alacrity and opened a clear lead after a few strides. Martin has said that Groovy can run a 44-second half-mile whenever he wants; today he went in :44 1/5.

The rival who had been expected to be his main challenger, Taylor's Special, never got into contention. He took a bad step on the turn and jockey Pat Day pulled him up. Purple Mountain was left to chase the favorite. All he could do was hold second place over Sun Master.

New York racing officials placed special security around Alysheba's barn and gave the colt an extra pre-race blood test after receiving a tip that he might be administered an illegal drug before the Travers.

At noon on Saturday, the stewards at Saratoga received a phone call from the New Jersey State Police at Monmouth Park, who had gotten information that Alysheba might be given endorphin, a medication that is a natural painkiller and not permitted in New York.

The stewards contacted trainer Jack Van Berg, who assured them he had no intention of administering anything to Alysheba. "Van Berg was very cooperative and grateful for the information," a steward said.

A blood sample was taken from Alysheba before the race and proved negative. Post-race tests are sent to the state testing facility at Cornell University; results will be known in a few days.

Alysheba finished a distant sixth over a muddy track in the Travers, his worst performance of the year.

Pimlico:

Bal Du Bois was last entering the stretch in the $73,600 Harbor Place Stakes, but Vince Bracciale guided her spectacular run through traffic to win going away, finishing a length ahead of Yampacala. Arctic Cloud was third, 3 1/2 lengths back.

Yampacala's jockey, Ron Franklin, claimed foul against the winner for interference nearing the finish line; the claim was disallowed.

Bal Du Bois, owned by Elsie Thompson of Charlottesville, ran the 1 1/8 miles in 1:50 2/5.