Manager Kirk Gibson made the announcement Monday. He also says the right-hander is going to be followed in the rotation by righty Trevor Cahill, left-hander Wade Miley and free-agent signee Brandon McCarthy.
Arizona opens the seasons on April 1 at home against the St. Louis Cardinals.
Cahill was 13-12 with a 3.78 ERA last year. Miley finished second to Washington's Bryce Harper for NL Rookie of the Year after winning 16 games last year.