John Adams' NaÇve and Sentimental Music, which premiered in 1999, will not be performed as scheduled.

Robert Moir, PSO vice president for artistic planning, told the Pittsburgh Post-Gazette, "[The Adams] is a 47-minute piece that is profoundly complex. There is no way that someone who had not prepared the piece could do it in such short notice. We felt if we couldn't get someone to do the piece who had done this before, we shouldn't do it."

Moir hoped to get Alan Gilbert, David Robertson, Esa-Pekka Salonen or David Zinman, who have previously conducted the work, to replace Spano, but none of them were unavailable.

Lars Vogt will perform Mozart's Piano Concerto in A major as originally planned; Debussy's Petite Suite and Dvorak's Symphony No. 7 will replace the Adams.

As the latest conductor casualty, Spano is in illustrious company. Due to a shoulder injury requiring surgery, James Levine has cancelled weeks of engagements including numerous Met and Boston Symphony performances. Earlier this month, Christoph von Dohnšnyi cancelled four concerts with the New York Philharmonic, while Kurt Masur fell ill with a viral infection in Dublin.