Virtuosity is rare in both the jazz and classical worlds, and trumpet player Wynton Marsalis is determined to be the best in both of them.

The two techniques are seemingly incompatible--the technical mastery of classical versus jazz improvisation, memory and concentration versus externalized imagination--but Marsalis seems to have them under control. The 20-year-old trumpet virtuoso has burst onto the jazz scene, harvesting a field full of laurels and trying to survive a built-in legend that has connected him to such masters of the idiom and instrument as Miles Davis, Dizzy Gillespie and Clifford Brown. Yet when Marsalis signed with Columbia Records, it demanded an album of classical trumpet on its Masterworks label, as well..

Of his twinned passions, Marsalis says, "To me, it's like playing football and then going to play basketball. They're both the same thing--sports. If you play football, you know that you're not going to bounce the ball on the ground. If you grow up playing sports, it's not really a great transformation. It's the same with music; it's not something I have to think about."

Marsalis, who will perform as part of the New York Hot Trumpet Repertory Company at the Pension Building on Sunday, may be caught up in the dichotomy of mastering divergent styles of music, but there's little doubt where his heart lies. "I grew up playing jazz and studied classical music. That's the only way to do it. If I'd grown up studying classical music and then tried to learn jazz, I'd be in trouble."

Born in New Orleans, Marsalis grew up exposed to marching bands, funk and soul bands, and classical orchestras, as well as the piano stylings of his father, Ellis Marsalis, a well known educator and local jazz figure.

Marsalis' first trumpet arrived when he was 6, a gift from Al Hirt, but the sense of purpose didn't arrive for another half-dozen years. From 14 to 16, Marsalis spiced up his re'sume' by appearing with the New Orleans Philharmonic and New Orleans Civic Orchestra, performing trumpet concerti by Haydn and Bach.

His 17th summer was spent at the Berkshire Music Center at Tanglewood, Mass., which for the first time exempted its 18-year age limit and rewarded Marsalis' virtuosity with the outstanding brass player award. He seems angered at misconceptions that jazz players aren't as serious as their classical counterparts. "You find out that classical musicians are like all other musicians," Marsalis has said. "Most of them are mediocre and a handful are excellent. I know it's harder to be a good jazz musician at an early age. In jazz, to be a good performer means to be an individual, which you don't have to be in classical music."

Despite his youth, Marsalis is a veteran of two disparate but distinguished finishing schools: the Juilliard in New York and Art Blakey's Jazz Messengers, a road school. "You can't even say the name jazz in that building," Marsalis says of Juilliard. "They don't know that I exist, they didn't know me as a jazz musician. Juilliard is memorization, knowledge, retention. Blakey, you just play and learn how to play. Juilliard allows for no technical mistakes; they don't really allow for any mistakes, which is why so many people go crazy over there. Blakey's not even concerned with mistakes; he's concerned with music only, period."

Marsalis' style is rooted firmly in the past--Lee Morgan's gritty and controlled inventiveness, Art Farmer's and Miles Davis' lyric sensibility, Freddie Hubbard's and Clifford Brown's warmth and strength. About the only thing he doesn't have at this point is patience with those who find him lacking as an innovator.

"People worship anything that's in the past," he says, exasperated. "That makes it much more difficult for you to come back and play something that they consider theirs. Hey, who broke new barriers when they were 20? Did Bird Charlie Parker do that? And he was a genius! Why is it in American music jazz everybody has to be an innovator instantly and in classical music, it's cool for somebody to play Bach? If they applied jazz standards to classical music, no classical musicians would be worth s---. Who's playing something new? Let me know, so I can hear them."

Marsalis seems unswayed by the critical hype or the weight of the reputation that places him squarely in a line of succession that starts with Gillespie and runs in ten-year cycles through Brown, Davis, Hubbard, Woody Shaw and, now . . . Wynton Marsalis.

"The music makes you humble," he says quietly. "All you have to do is put on a Miles album or Freddie Hubbard or Don Cherry playing with Ornette Coleman and that automatically makes you humble because you listen and you know you can't play that well. I'm just trying to keep it together, that's all."