Star de Naskra, a colt who has spent most of his life in the grim surroundings of Bowie, came here today to show whether he belongs in the upper echelon of horse racing.

He proved it convincingly. Star de Naskra raced to a brilliant victory in the $100,000 Whitney Stakes, beating Cox's Ridge by three-quarters of a length, and established himself as one of the most gifted thoroughbreds in America.

A late-blooming 4-year-old, Star de Naskra had finished first in his last six starts (with one disqualification), but had still not fully persuaded trainer Dick Ferris how good he was. At first Ferris considered him to be principally a sprinter, and decided to pursue the national sprint championship. After he won several short races in New York, Ferris decided to try him in a weak 1 1/8-mile stakes race in Nebraska.

"He won so sensationally," the trainer said, "that I decided, well, we ought to try the heavyheads."

There were plenty of heavyheads in the Whitney. Cox's Ridge was one of the best horses in the country last year, and was now returning to peak form after an injury. State Dinner had won two-thirds of New York's "handicap triple crown." Text has been a star on the West Coast.

But Star de Naskra handled them all. He broke alertly, as usual, but didn't have to exert himself to take the early lead. "We wanted to slow down the early fractions," jockey Jeffrey Fell said, and he accomplished just that. Star de Naskra led after running the first half-mile in a dawdling 48 1/5 seconds.

The other five jockeys in the field recognized what was happening, and knew they couldn't wait. Jean Cruguet rushed Text up along the rail to take the lead, while Cox's Ridge and The Liberal Member loomed up on the outside. They raced through a sizzling third quarter in 22 3/5 seconds, and they turned into the stretch four abreast.

Cox's Ridge gained a momentary advantage, and many people in the crowd of 23,128 may have thought he was about to pull away. But Fell knew differently. "Star de Naskra really had his mind on running," the jockey said. "Going that slow early really left him with a solid kick."

When Fell start using the whip, Star de Naskra started inching away from his determined opponent, and at the wire he was drawing away with every stride. He had covered the 1 1/8 miles in 1:47 3/5, three-fifths of a second off the track record.

Star de Naskra paid $4.20, $2.60 and $2.20. Cox's Ridge returned $3 and $2.69. The Liberal Member, who finished another half-length behind, paid $2.80 to show.

The victory told a lot about Star de Naskra that he had not proved in his six prior victories. The colt showed that he is not merely a sprinter, that he can run a distance against top-class competition. Nothing in his performace suggested that even a 1 1/4-mile race would be beyond his capabilities. And he also show that he has a competitive spirit as great as his raw abilities.

The colt's development has been a dizzying experience for Ferris, who has spent much of his career saddling cheap claiming horses at Bowie. "I haven't handled any horses like him before," the trainer said. "But this year he's matured and gotten completely relaxed. He's got confidence. He thinks he can beat anybody."

In a few weeks Star de Naskra will have the chance to prove he can beat anybody.Ferris said he will probably run him in the Marlboro Cup at Belmont Park, against Affirmed and possibly Spectacular Bid, a confrontation that will help determine the Horse of the Year title.