Ivan Vasiliev, the Bolshoi Ballet whiz kid who was a star of their Kennedy Center season last weekend, may have a fine future in front of him. Or he may burn out very quickly. Eighteen-year-old Mr. Vasiliev joined Moscow’s Bolshoi earlier this season, months after graduating from the national ballet school in Belarus and winning the grand prize at the high-visibility Varna competition in Bulgaria. On both Saturday and Sunday afternoon he danced Basilio in “Don Quixote.” I saw his Saturday performance.

Winning ballet competitions requires skills that are often at odds with what’s required to be a great artist on the ballet stage, but Mr. Vasiliev succeeded in dancing with some finesse and in adjusting to the context of a theatrical rather than competitive event. He is very short, but his proportions are good enough and his movement expansive enough that he doesn’t seem impacted. To his credit, Mr. Vasiliev did as much acting as he needed without forcing a lot of personality projection or trying to manipulate the audience by looking adorably and adolescently befuddled.

His technique is certainly virtuosic, but there’s also no question that it belongs to the fling-and-flail movement that now dominates so much ballet. The exploitation of immature dancers is now more widespread and pernicious than ever before, and fling-and-flail is almost always the way very young dancers approach movement, by virtue of both their hunger to make effects and the still-limited degree of élan and coordination of which their bodies are capable. But Mr. Vasiliev demonstrated a very high quality fling-and-flail.

Nevertheless, there was some slackness to his attack in Act I, and a reckless landing from a jump in Act II, both of which made clear that like most very young performers, Mr. Vasiliev needs, to some extent, to be protected from himself.

Mr. Vasiliev’s Kitri was 21-year-old Natalia Osipova — New York saw her during the Bolshoi’s summer 2005 season, where she was phenomenal in this same ballet dancing one of the interpolated solos that grace the company’s Act III wedding celebration. Kitri is an ideal role for her because her jump is outrageous: Not only is it extraordinarily high, but demonstrates, to an unsurpassed degree, the balletic ideal of “ballon” — the dancer’s ability to pause suspended in the air. And Ms. Osipova’s jump has a unique singing, surging quality. On Saturday afternoon, every aerial move she made — small, large, solo, or supported — was riveting.

But although Ms. Osipova has been dancing the role for about a year now, her performance is still raw. She had evidently been coached to respect the different aspects of Kitri manifested throughout the three acts — from willful, mischevious flirt to dream apparition to radiant young bride and grand ballerina — but she was not able to make them her own or even delineate them with any real depth. In Act I, her vivacity too often seemed strident.

Technically, though, she came into her own in the last act, dazzling with very fast passes in her solo and an incredible volley of multiple fouéttes in the coda, which she accomplished without sacrificing her form.

Saturday night the grown-ups took over, when Kitri and Basil were danced by Maria Alexandrova and Denis Matvienko, who are both in their late 20s. Ms. Alexandrova is one of the world’s great ballerinas and one of the world’s great Kitris. There was an anomalous note of caution to her Act I castanet solo, but otherwise she danced with an abandon that went hand in hand with apparently limitless physical resources as well as faultless taste in shaping and presenting every contour of classical style. She has grown in the role since New York saw her dance it with the Bolshoi during their summer 2005 season; her fickle flirtations and relentless obstinacy in Act 1 never obscured the fact that she was a woman deeply in love.

Mr. Matvienko was seen to far better advantage here than in his two New York gala appearances over the last year. He was technically exciting and his acting and presence were ingratiating. His arms, however, were never more than generic in a ballet that is emphatically Spanish-styled, and he had difficulty presenting himself as a stage figure equal in importance to Ms. Alexandrova. Like Mr. Vasiliev, he was imported by the Bolshoi. Trained in Kiev, he has spent the last four years dancing around the world as a guest artist. He would do well to settle down and avail himself of the opportunities for coaching and self-perfection offered by a company like the Bolshoi.

Saturday night’s performance as a whole caught fire even more than that of the matinee, though both were superbly danced by the entire Bolshoi troupe. The boleros and fandangos and gypsy dances were wonderfully performed, as were the classical interludes. Once renowned for its often crude flamboyance, the Bolshoi is still robust but has become remarkably well mannered of late, part of the reason it has enjoyed a renaissance during the past few years.