It was Sir Frederick Ashton, Great Britain's grandmaster of the classical ballet, whose genius illuminated the stage Wednesday night at the Kennedy Center Opera House, as the Joffrey Ballet opened its two-week engagement with a salute to the 80-year-old choreographer. And once again last night, during the second Joffrey program, an Ashton work captured a special place of honor.

The piece in question was "Five Brahms Waltzes in the Manner of Isadora Duncan," a series of solos created in 1976 for the superb English dancer Lynn Seymour. Ashton had seen Duncan dance in London when he was 17. The tribute is a distillation of his memories -- an impression rather than a re-creation -- and eloquent testimony to Duncan's profound impact on him, set to music he'd seen her dance to. For the Joffrey, Seymour taught the role to ballerina Jodie Gates.

Recalling Duncan, Ashton has spoken of "enormous grace," "enormous power," and "an extraordinary quality of repose." He also remembers "a wonderful way of running, in which she what I call left herself behind, and you felt the breeze was running through her hair and everything else . . . she wasn't really the old camp that everyone makes her out now, she was very serious and an immensely strong personality that came right across the footlights and held the audience and compelled them completely." Seymour's interpretation of the "Five Waltzes" was a wonder in itself -- how much it had to do with the real-life Duncan is hard to say for those of us who lack firsthand acquaintance, but it so closely matched the pictorial and historical records that it seemed sublimely convincing.

Gates' rendering last night proved that Seymour must have been a splendid teacher and Gates a receptive pupil. It was a young performance, and it lacked much of the soulful nuance of the mature Seymour -- one has to keep in mind also that Duncan was 44 when Ashton saw her. But Gates had the right fullness of body and caught the free lyrical spirit, the weighted flow and the ecstasy of Ashton's poetic homage.

Like "Five Brahms Waltzes," Gerald Arpino's "Jamboree" received its Washington premiere last night. The ballet, commissioned by the city of San Antonio, is an extravagant pastiche of imagery and motifs drawn from the Mexican-Hispanic, Indian, and American cowboy cultures of the Southwest. Teo Macero's tangy score uses folk tunes and such instruments as harmonicas, banjos and maracas to spice up the local flavor.

There are six sections, including an opening "fancy dan" solo for stalwart Edward Morgan, who happens to be a San Antonio native; a contrasting pair of amorous duets; a sprightly clog-tap number for Tom Mossbrucker and David Palmer; a "passion play," depicting a young man's (Luis Perez) frenzied devotion to the Virgin of Guadeloupe; and a rip-roaring virtuoso finale for 19 dancers. The performances were wonderfully infectious, and the ballet benefited from Arpino's shrewd calculation of effects. Though it's appreciably less dizzying in pace and structure than much of Arpino's work, in the end it seems no less fluffy and insubstantial, for all its color.

Also on the program was Arpino's moodily rapturous "Round of Angels," which won a deserved ovation for principals Patricia Miller and James Canfield. The evening began with Jiri Kylian's syrupy panegyric to folk dance, "Dream Dances," splendidly set forth by its large cast.