Composers listed in the Ozawa Hall program were Haydn, Beethoven, Stravinsky and Ives — and don't stop reading. Cellist Yo-Yo Ma and pianist Emanuel Ax performed the Beethoven and Ives — keep on reading, you'll see.

It wasn't even a concert. It was the annual collaboration (Wednesday, repeated Thursday) of the Mark Morris Dance Group and the Tanglewood Music Center. Morris makes dances for his group, rehearsing at Jacob's Pillow, and Tanglewood fellows — plus faculty — perform music he has chosen to set. What Ma and Ax played were billed as premieres, because the dances, "Visitation" and "Empire Garden," were new dance settings by Morris, to be repeated next week at Lincoln Center's Mostly Mozart Festival.

Audacious choreography of a cello and piano sonata by Beethoven was heightened by the piano's placement half offstage, so these mega-famous artists played virtually underneath the Exit sign. Make no mistake, they loved it, and applauded the dancers heartily. Call it prejudice, but it did seem that the dancers were buoyed by the rich, immediate sound of world-class backup.

The Ives Piano Trio, a crazy-quilt Americana medley, was co-commissioned by Lincoln Center and Tanglewood. (Violinist Colin Jacobsen is a member of Ma's Silk Road Ensemble.) Costumes mixed circus and military, mirroring Ives' duality of keys and colliding music worlds (click HERE).

Concert audiences are by definition musically savvy, and Morris, who listens to music so deeply that his dancers have to memorize score rehearsal numbers, probably guessed that this wouldn't play at the Pillow. For two nights, it sure did at Tanglewood.