Recent memory can conjure few concerts to match the exhilaration and musical depth of pianist Valeri Grohovski's performance Saturday night at the Instituto de México in a program of jazz standards and jazz interpretations of J.S. Bach.

Grohovski's first-class, superbly responsive rhythm section - or the continuo, if you prefer baroque terminology - comprised bassist Hamilton Price of Austin and drummer Gerry Gibbs of San Antonio. The concert inaugurated the institute's brand-new, 7-foot-long Steinway, which sounded rich, clean and well-balanced, ideally suited to the small auditorium.

The remarkable first half held Grohovski's jazz trio arrangements of Bach's Partita No. 1 in B-flat and Concerto in D Minor. As arrangements go, these were exceedingly modest in their interventions. The printed score left most of Bach's original music unaltered. Most of the magic was created on the fly, though according to a general plan.

Grohovski, who formerly spelled his name Grokhovski, began most movements of the Bach pieces by playing the notes that Bach wrote, in a crystalline, precise and firm technique that would have pleased any baroque purist. But then the rhythms would subtly shift into a swing, or Grohovski would introduce a harmony or an ornament from the jazz tradition. And sometimes Price would play a sultry blues line - which came directly from Bach's pen.

The widest detour from the original score and style came in the Sarabande of the partita, which Grohovski reconceived and partly recomposed as a melancholy jazz ballad - not much of a stretch for the Bach melody. Gibbs pumped up the poignancy with gorgeous tempo play. The slow movement of the concerto fell into similar territory.

Elsewhere, baroque Bach and jazz Bach flowed into each other seamlessly, and always with respect for both traditions. The result was not just a parlor trick, but a mutually illuminating accord. Listeners seeking sheer dazzlement had plenty of ear candy. In both Bach works, Grohovski applied his peerless combination of gigahertz speed and unflagging sense of direction to incandescent finales.

The concert's second half gave evidence that Grohovski has grown immeasurably as a jazz thinker over the past decade.

He was probing much more deeply into the music, improvising more imaginatively and drawing more freely on received traditions than in the past. His stride style, heard for example in his unaccompanied "Over the Rainbow," was more nuanced and flexible than in the past.

His penchant for complexity and superhuman speed was still audible on Saturday - in Cole Porter's "Just One of Those Things," he spun interweaving lines that one might have thought executable only by a computer-controlled piano.

If jazz illuminated Bach in the first half, Bach returned the favor in the second when Grohovski opened Nicholas Brodsky's "Be My Love" with supple baroque counterpoint.