Arthur Fennimore's piano received yesterday afternoon at the Phillips Collection was a fine blend of intellectual insight and emotional expression.

The Pennsylvania-born pianist last played here in 1965. Still earlier he was a finalist in the first Cliburn Competition in Fort Worth in 1958, when his playing had those qualities that were clearly present yesterday.

His singing tone, commanded at will, is a lovely lyric gift. And in music such as the next-to-the-last Beethoven sonata, he showed that he knew the great secret of taking plenty of time to let the music grow. Dividing the Beethoven from the Chopin Opus 25 Etudes that closed the concert, Fennimore placed the Partita-Variations by George Rochberg, written for the Washington Performing Arts Society during the Bicentennial season and first heard here that year.

These were as captivating yesterday as at their first hearing.Indeed, Fennimore brought out of them a kind of lightness, almost a whimsy, that had been less apparent a year ago as he fully revealed Rochberg's skillful writing and brilliant ideas.

Nearly a decade ago Fennimore suffered an injury to his hand while in military service at West Point. This is the first year since then that he has performed in concert. There were times yesterday when some notes stubbornly refused to fall into place. But in the total scheme of things, it seems likely that these will like care of themselves as Fennimore returns to full activity.