Lux was held back in extended spring training as he works his way back from a rib issue, MLB.com's William Boor reports.
Lux was likely ticketed for Low-A Great Lakes, but suffered some sort of rib injury this spring, which will delay his full-season debut. He is a true shortstop, and has a knack for making consistent contact, but it is unclear what kind of power he will grow into down the road.