This week’s sold-out concerts by the San Francisco Symphony, featuring Itzhak Perlman as conductor and violinist in a program of Mozart, Tchaikovsky and Brahms had to be modified over the weekend when Perlman said he is too ill to perform.

Music Director Michael Tilson Thomas comes to the rescue in the sudden change of plans. He will conduct a program including the originally scheduled Brahms Symphony No. 2, plus Beethoven’s Piano Concerto No. 1, with Jeremy Denk as soloist and “King Stephen” Overture.

The concerts are at 8 p.m. Wednesday, Thursday and Saturday, and at 2 p.m. Sunday in Davies Symphony Hall at Van Ness Avenue and Grove Street. Call the Symphony at (415) 864-6000 to buy, exchange or return tickets.