Former NFL first-round pick Robert Nkemdiche found himself in some trouble last week … when cops say they saw him walking out of a store with groceries in his pants — but it was past run-ins with the law that got him put in the slammer.

According to a police report, obtained by TMZ Sports, the former Arizona Cardinals defensive tackle was exiting a Kroger in Georgia last week … when an officer conducting a business area check says they observed the 31-year-old with “many large objects, square and rectangular shapes, consistent with concealed grocery items, inside his sweatpants.”

The officer says they then called for backup as Nkemdiche walked to a gas station.

Officers say they then ran Nkemdiche’s name and found multiple warrants in several states in the system … including three in Georgia. The officer says county officials asked the officer to place a hold on Nkemdiche.

The former Ole Miss star was ultimately taken to jail and booked.

Nkemdiche was previously busted for drug possession in 2015 … after an incident where he allegedly fell from a fourth-floor window of a hotel.