Amid the gray chill at Laurel yesterday, the promise of spring flashed before Jerold Hoffberger and trainer Dennis Potts. Fappavalley, their improving 3-year-old colt, closed with a flourish to win the $53,600 Star De Naskra Stakes by 3 1/2 lengths over Fair Royale.

The seven-furlong victory in 1:24 2/5 marked Fappavalley as a Kentucky Derby hopeful. His veteran rider, Jesse Davidson, said, "He's the best {3-year-old} I've been on in a long time."

Bred and owned by former Baltimore Orioles owner Hoffberger, Fappavalley is the product of regal bloodlines. His sire, Fappiano (a son of Mr. Prospector), commands a $125,000 stud fee; his dam, Seven Valleys, was a stakes-placed filly.

Despite his promising origin, Fappavalley was not an immediate success. In his first start, Sept. 20 at Pimlico, he was pinched leaving the gate and beaten by 18 lengths. Moreover, he bruised muscles and was laid off three months.

In his return, Dec. 14 at Laurel, Fappavalley's ability was illuminated. The speedy Full Security, alone in front from the start, carried a four-length lead into the stretch. But Fappavalley caught him by midstretch and swept past for a four-length triumph.

Yesterday, in a six-horse field, his task of rallying was simplified. Davidson kept Fappavalley in fifth as a four-horse speed duel developed before him.

Favored Gospel Note was among those vying for the lead, and he shook off Gina's Double, Nile Jewel and Circus Maximus into the turn. At that point, Fappavalley was making up ground on the outside and, by the top of the stretch, had the front-runner well within reach. "I hit him once," Davidson said, "and it was like I had a new horse."

Fappavalley cruised past Gospel Note, and Fair Royale followed in kind to gain second.

"{Fappavalley} has shown us {a Triple Crown nomination} definitely should be considered," said Potts, heretofore without a stakes victory. "He's not fully mature, so . . . we don't want to get too greedy or too ambitious with him. But I think the longer he goes, the better he'll be."

Hialeah Park:

French-bred Double Bed, who raced in the 1986 Washington, D.C. International, won the $200,000 Hialeah Turf Cup over Salem Drive in Miami.

In Arcadia, Calif., Conquering Hero edged Smoggy by a neck to win the $111,500 San Gabriel Handicap at Santa Anita. Ten Keys, a Maryland-based colt, finished third, three-quarters of a length back.