In her prime, she was a national heroine and a martyr. But the end of Genuine Risk's career yesterday came as something of an anticlimax.

Since her victory in the Kentucky Derby and her memorable campaign in the Triple Crown series, the filly had made a number of abortive comeback attempts. Her efforts were hampered, however, by apparent problems in trainer LeRoy Jolley's stable as well as her own physical infirmities.

As Genuine Risk was preparing for a confrontation with Pleasant Colony in the Woodward Stakes at Belmont Park Saturday, she seemed to be favoring a sore left foreleg. "There really wasn't much choice," Jolley said. "It's something that had to be done."

The filly left Belmont at 6 a.m. and was sent to owner Bert Firestone's farm in Waterford, Va. "I'm sorry to see her retired, but I'm looking forward to her offspring," Firestone said. "Her injury was nothing serious but with her we didn't want to take any chances at all."

Bought as a yearling for $32,000, Genuine Risk became a celebrity when she made a powerful move on the final turn and won the 1980 Kentucky Derby; she was only the second filly in history to accomplish the feat. Two weeks later, she got sympathy as well as admiration when Codex bumped her in the Preakness but withstood a foul claim and a subsequent hearing by the Maryland Racing Commission. Across the country, newspapers described the incident with headlines like "A Lady Mugged."

Genuine Risk also finished second in the Belmont Stakes, becoming the first member of her sex to race in the entire Triple Crown series. But the stress of those races evidently took a toll. In the last 15 months, the filly raced only five times.

She certainly was not helped by the general turmoil in Jolley's barn. Firestone fired Jacinto Vasquez, the jockey who had ridden Genuine Risk through her whole 3-year-old campaign. And Jolley was preoccupied by his 198l Derby candidate, Cure the Blues, who performed far below expectations and also was retired this year.

Genuine Risk raced at Saratoga a month ago in an allowance race staged largely for her benefit, and she won it in a fashion that suggested she might be recapturing her best 1980 form. That event was supposed to be a prep for the Woodward, but it proved to be an unceremonious end to her career. She retired with 10 victories in 15 lifetime starts and earnings of $646,587.