Williams will start Monday's tilt with the Dodgers, Adam Berry of MLB.com reports.
Monday's start was initially going to be for Jameson Taillon (groin), but after Taillon was placed on the disabled list Saturday, Williams will move into the rotation to replace him this time around. The 25-year-old's command has been a bit shaky over his past few relief appearances, but he'll look to bring his success from his minor-league starting days (2.53 ERA, 1.21 WHIP at Triple-A in 2016) into his upcoming appearance when he faces off against Alex Wood.