Pettibone (shoulder) was assigned to minor league camp on Monday, the Chicago Sun-Times' Gordon Wittenmyer reports.
He did not pitch in any spring games for the Cubs, likely due to the fact that his shoulder still isn't right after needing a second surgery on that right shoulder in July. When healthy, he should head to Triple-A, and while he has always been a starter, the Cubs may look to convert him to a reliever.