Veteran San Diego pitcher Tim Stauffer will begin the season with triple-A Tucson, according to MLB.com.
The right-hander is returning to the mound after elbow surgery cut short his 2012 season. He was limited to one start and five innings last year.
Stauffer, 30, is still working his way back from the injury. In six appearances this spring, he has an 8.74 ERA.
Before the injury, Stauffer turned in his best years in San Diego from 2009 to 2011, posting a 15-17 record that included 31 starts in 2011 and 32 appearances in 2010.
The Padres also assigned right-hander Sean O'Sullivan, catcher Juan Rivera, outfielder Travis Buck and infielder Gregorio Petit to their minor-league camp.