Of the recent spate of young Russian performers to come to the West, none has created a greater stir in musical circles than the beautiful, brilliant violinist Viktoria Mullova. Reports of her extraordinary talent started flowing soon after she crossed into the West while touring Finland in July 1983, a year after attaining that ultimate prize of music, the gold medal in the Tchaikovsky Competition.

She finally made it to Washington Saturday afternoon at the Kennedy Center, playing the Sibelius "Concerto in D" with the Boston Symphony and Seiji Ozawa. On the basis of this performance alone, it is clear that Mullova is equipped for a major musical career. She is the most impressive new Soviet violinist to arrive here since Gidon Kremer.

The moody, driven Sibelius work, one of his two or three mightiest, is an ultimate test for a violinist. And if one is up to it, the concerto is a particularly appropriate vehicle for a debut. It has all the fiery pyrotechnics of the standard virtuoso showpieces, but there is also an intensity of feeling that poses a meaningful measure of a player's interpretive depth.

Mullova, who is 26, was quite impressive in both respects, a fabulous player.

She produces a very big sound, with lots of strength but no unintended hard edges. And her agility, as she dived into that first movement nest of bold legato leaps -- sixths and octaves especially, which are a formidable test of any player's accuracy -- as beyond question.

Interpretively, it was a more pensive performance than some I have heard. She did not push the ferocity of the first movement as hard as some players have -- Heifetz, for instance.

The haunting, meditative mood she brought to the slow movement was truly moving. This is a rather vocal movement and she played like a fine singer, quietly and intensely.

Mullova, a striking figure in her black pants suit with her dark hair pulled back into a pigtail, faced the awesome articulative demands of the finale, the one Tovey called "a polonaise for polar bears," unblinkingly.

Thematically and structurally this concerto is a grand achievement, but the mood is set as much as anything else by Sibelius' timbral mastery, by stark contrasts of light and dark that capture so memorably the bleakness of his native Finnish landscape. Sibelius juxtaposes the silvery, high purity of the violin against the shadowy, gritty background of the orchestra's low winds and brasses in a way that suggests a solitary spirit wandering in the deserted wastes. It is a memorable evocation of tenderness against heroics.

And the Boston's winds, which are as fine as any in the world, caught the sound exactly right.

The other work was another great one that happens to be similar in mood as well as sound, a suite of music from Prokofiev's ballet "Romeo and Juliet."

I don't know how many Boston players are left now who go back to the legendary Koussevitzky era (1924-1949), when the Boston Symphony was the world's greatest Sibelius and Prokofiev orchestra, but that Koussevitzky stamp is still on the Boston Symphony -- especially that dark sound that was one of the essentials of the Koussevitzky sonic vocabulary.

An example: the perfect dynamic control and richness of the massed strings in that ecstatic section for Juliet's funeral, attacks and releases absolutely precise -- and once again, lights and darks so precisely juxtaposed.