Grichuk was scratched from the lineup for Sunday's game against the Brewers due to lower-body tightness, Alex Weiner of ArizonaSports.com reports.
Grichuk was scheduled to start in left field and bat third, but the back issue will instead keep him out of the lineup. The veteran outfielder is expected to be available off the bench, so he doesn't appear to be dealing with a serious injury. Pavin Smith is instead starting in left field for Arizona.