It was hard to believe the asterisks on the National Symphony program last night-three of them, indicating "first performance by the National Symphony"-opposite a symphony by Haydn and concertos by Haydn and Mozart.

But the asterisks were right. Max Rudolf, coming in on short notice for the indisposed Leonard Bernstein, brought NSO subscribers three beautiful works of Haydn and Mozart.

First came the Symphony No. 91 by Haydn, one of the works the composer himself regarded as "mellow." Its E flat tonality is just right for the elegance of its thought. It is rich in dynamic contrasts with which Haydn lightens up its contours, and you should hear the pair of bassoons light-heartedly singing away in the menuet's trio.

Rudolf made the National Symphony's first playing of the symphony a matter for hope that the second may not be long in coming. The orchestra's response was excellent, and the brio in the finale sheer delight.

Then there was Barry Tuckwell. With his celebrated horn, the great English virtuoso played a Haydn concerto in D and the second of the Mozart concertos. With the orchestra reduced as it was in the Haydn symphony, and joined by the harpischord for the Haydn concerto, Tuckwell turned in a performance filled with brilliant trills and an astounding command of dynamics, tossing off some very tricky passages so fluently you hardly realized they had passed.

With the Mozart concerto especially, Tuckwell displayed a flawless legato line and the sublest kind of shading, all with a sense of ease that defied the horn's reputation for making trouble. The audience hailed him and Rudolf, who provided model support, over and over.

The Schumann Fourth Symphony closed the evening in solid fashion. The concert is being repeated nightly through Friday.