Concerts by that priestess of the piano, Alicia de Larrocha, are taking on the patina -- a special chemistry between player and listeners -- of the musical rite. The rapport comes, in considerable part, from annual repetition. Saturday night's recital at the Kennedy Center was the 10th time de Larrocha has appeared here for the Washington Performing Arts Society, quite aside from her many other concerts in the city.

One does not attend just to hear the music, in this case Grieg, Espla' and Schubert. One goes to hear a musical style, a manner so distinctive that it is safe to assume that no other artist can quite duplicate it, just as is the case with Rudolf Serkin or was, in the recent past, with Rubinstein.

On Saturday, de Larrocha's playing was radiant. It is a phenomenon that includes startlingly clear textures (who else can pedal as heavily as she does and yet keep everything so crystal clear?); amazing articulation (all the more so for the fact that she seldom plays very loud); unfailing tonal allure and uncompromising musicality. There is an uncanny balance of clarity and joie de vivre reminiscent of the finest Impressionist painting.

In the dominant work, Schubert's great B-flat Sonata, Op. Posth. -- a piano sonata of truly religious import -- de Larrocha mixed incredible evenness in the work's expansive rhetoric with the subtle sensitivity to the underlying harmonic tensions.

Unlike most pianists, she played the repeat of the opening movement's lengthy exposition, and one was struck with how many of the most minute details were heard the second time just as they had been played before. Perhaps there was the illusion of spontaneity, but if you listened closely there was nothing casual.

As is often the case with a de Larrocha program, the remainder of the concert was of little-known music.

A fairly brief Grieg E-minor Sonata, Op. 7, was a product of his youth, full of romantic ardor and clearly a case of Liszt-worship. It sounds a bit like early Brahms -- more Germanic than Scandinavian. Perhaps the sonata does not add up to greatness, but it has some lovely material, especially in the hands of de Larrocha.

A Sonata espagn ola by the little-known 20th-century Spaniard Oscar Espla' was even more appealing. The composer, who died in 1976, was prominent in UNESCO in its early days and was commissioned by that organization to write this work as a memorial to Chopin on the centenary of his death.

Combining Polish elements (the middle movement is called "Mazurka sopra una tema populare") with Spanish elements may seem strange, but, in its unostentatious way, the piece had intensity and character. Listeners were reminded by the performance that de Larrocha's way with Spanish music is unique.