"A sore back; it's just tight," Ventura said. "It's one of those he's trying to work it out right now. He won't start. Hopefully he can pinch hit."
Konerko was slowed by a bad back during spring training, but Ventura said this issue was not related. The team captain also missed time with a sore neck earlier this month.
Ventura has been careful to not overuse the 37-year-old Konerko. The normal everyday first baseman has been in the lineup 33 times as the designated hitter and 34 times as the first baseman.