Williams will be a reliever for the Cubs at least until the All-Star break, Meghan Montemurro of the Chicago Tribune reports.
If Jake Arrieta's struggles persist, it's possible he yields his spot in the rotation to Williams sometime after the break. Williams hasn't excelled either this season, pitching to a 5.36 ERA and tallying just two quality starts in 10 outings. The Cubs' rotation plans should become more clear next week as the second half begins.