Hauling out a word like "stunning" to characterize a particularly brilliant performance -- as in pianist Lambert Orkis' solo playing with the National Symphony last night -- can be an injustice to the player, much as it may look good in lights.

The music making by Orkis, who is best known to audiences here as "principal keyboardist" in the National Symphony, was stunning. Some of the articulation in Richard Strauss' unjustly neglected "Burleske," a fine work that is as close as the great man ever came to composing a piano concerto, was indeed breathtaking -- for instance, those alternating and ascending double octaves that came right at the end, impeccably crisp and even.

But there was considerably more to what Orkis achieved in the 20-minute course of the "Burleske" -- a mercurial composition that was written in the same year as the depths of "Death and Transfiguration." The "Burleske's" instant and unpredictable shifts from a sardonic mode to a lyric one, and back again, sound almost like an induced emotional antidote to the grimness of "Death and Transfiguration."

Orkis caught the flashes with deftness and rhythmic steadiness -- and a delicacy of wit. His music making simply took flight and never stopped.

Staff pianists in orchestras may sometimes have techniques like this one, but they aren't expected to be such stylists. The only comparable example that comes to mind is the late Paul Jacobs, a magnificent pianist who for years adorned the staff of the New York Philharmonic.

The glories of last night's concert did not stop with the Strauss. Conductor Rafael Fru hbeck de Burgos opened with one of those important works that are more heard about than heard, Max Reger's Variations and Fugue on a Theme by Mozart. Reger was a late-Romantic contemporary of Strauss and Mahler whose reputation has not flowered as theirs have with the passage of time.

The intricacies of his work are often quite brilliant, but they do not break into consistent expressive fluency the way theirs do. When it does, though, as in this work's eighth and final variation, it stirs the sensibilities as much as anybody's.

Maybe Reger was trying to do too much here, basing this set of variations on the familiar opening theme of Mozart's A-major piano sonata, K. 331, and clearly emulating his hero Brahms' mighty Haydn Variations. Much of it is a little too stiff for its own good. But in this lengthy final variation, the music becomes rhapsodic, resembling the valedictory "Nimrod" section of Elgar's "Enigma" Variations -- high praise indeed. A suite from Stravinsky's "The Firebird" ended the evening.