Lopez will start Wednesday's game against the Twins in Minnesota, Vinnie Duber of NBC Sports Chicago reports.
Over his five seasons with the White Sox, Lopez has picked up 82 starts, but he's found a niche as a high-leverage reliever in his eight appearances out of the bullpen in 2021, logging a 1.29 ERA in 14 innings while limiting opposing hitters to a .146 average. He'll be thrust into starting duty on short notice while the White Sox rejigger their pitching schedule following Carlos Rodon's (shoulder) move to the IL, but expect the White Sox to limit Lopez's workload. He'll be pitching on two days' rest and hasn't covered more than three innings since getting a call-up from Triple-A Charlotte in mid-July, so Lopez shouldn't be expected to go through the Minnesota batting order more than once. Michael Kopech -- who hasn't pitched since Saturday -- could be a candidate to work multiple innings behind Lopez.