Ducere won yesterday's Primer Breeders' Cup at Laurel, but the outstanding achievement on closing day went to Sharp Image, a flighty filly who ran off before the second race and then fled to victory.

Sharp Image hadn't raced before, and appeared as if she had no desire to do so yesterday. She froze in the middle of the racetrack as her groom walked her to the paddock; then, cajoled to move on, she broke free after being saddled and sped three furlongs clockwise through the stretch.

Because Sharp Image wasn't winded, the stewards allowed her to run. Even assistant trainer Joe Furfure Jr. said, "I figured that would help relax her and get rid of some of that nervous energy in her system."

But Sharp Image remained insolent. She froze again after Joe Rocco climbed atop her, and the jockey quickly dismounted. "Once they freeze, it's scary because they're liable to do anything," Rocco said.

Coaxed out of her stance, the filly was ponied to the gate with Rocco aboard. Rocco said he wasn't worried about the inside-most post -- even with the inner rail so close -- because the filly had shown good speed in the mornings (although the only published workout failed to reflect it).

The gates emptied, Sharp Image burst to the lead, and no one got close to her. She won by about three lengths and paid $14.

"She had never made a bad move in her life," said Furfure, who directs trainer Bob Klesaris's Maryland division. "It's funny how horses react. This filly had taken to the track like a duck to water."

Even so, no one took a chance bringing Sharp Image into the winner's circle after the race, track photographer Jim McCue snapping the picture on the racetrack.

Ducere ($21.60) won the Primer similarly, breaking fast and winning comfortably. However, the John Salzman-trained 2-year-old had to weather a foul claim, Victor Molina alleging that Mario Pino shut off his horse, second-place Tammany, in the stretch. After a long review, the stewards ruled otherwise, honoring the victory for owner-breeder Guy Snowden.

Pino, who won with both his mounts yesterday, was successful in discouraging Molina from trying to pass on the inside early in the stretch by moving Ducere slightly toward the rail. "He had room," Pino said of Tammany. "I just kind of closed the hole up before he was there."

For the 31-day meeting, Laurel experienced drops in wagering and attendance. The average daily handle of $1,529,285 was down 4.5 percent over its 1989 summer dates; the average attendance, 9,844, was off 4.7 percent. After a day off today, Pimlico opens Thursday.

King Leatherbury won another training title with 23 winners, and Mark Johnston -- one day from losing his apprenticeship -- ended with 46 to lead riders. Unofficially, Ben Perkins Jr. was the top percentage trainer -- edging John Hartsell, 44.4 to 43.75 -- and Gregg McCarron the most proficient jockey at 20.9. Major Lux Destroyed

Major Lux, a rising 3-year-old who had won the Harbor Place Stakes in his latest start, was destroyed after breaking down in a workout Monday morning.

The big Maryland-bred was gearing for Saturday's Sir Ivor Stakes when he broke a foreleg on the Pimlico dirt. "He was breezing so good," said jockey Jorge Duarte, who is riding much of trainer Bernie Bond's stock for the injured McCarron. "When he went to switch leads, it snapped. I don't know how he pulled up."

A son of Majestic Light, Major Lux won five of 15 starts and $159,667 for Eugene Ford of Bethesda.