Down Corbin Burnes, the D-backs need Pfaadt to turn a corner and pitch like the arm Arizona extended in the offseason. Even if the ERA isn't sparkling, Pfaadt needs to show he can keep a handle on games and limit the hard contact.

Lauer has bounced back-and-forth between traditional starter and bulk reliever. He's faired better in the latter role with a 0.96 ERA in six appearances, but the Blue Jays will give him a traditional start against Arizona. With Bowden Francis (shoulder) out indefinitely, Lauer could get a long run in the Toronto rotation.

The Diamondbacks made a move to shore up their organizational pitching depth, signing right-hander Anthony DeSclafani to a major league contract and fitting him on the roster by optioning right-hander Bryce Jarvis to Triple-A Reno.