With one out and runners on second and third and Aaron Hill at the plate in the fifth, the skies opened up and umpires quickly called the game.
The Brewers got on the board in the first when former D-backs slugger Mark Reynolds singled home Logan Schafer, who had tripled to right.
The D-backs tied things up in the second when Mark Trumbo led off with a homer to left-center off Hiram Burgos.
Trumbo was back in the starting lineup one day after being scratched due to a bruised left heel.
The D-backs took a 2-1 lead in the third when Paul Goldschmidt drew a two-out walk from Michael Olmsted and scored when Miguel Montero followed with a double to the gap in right.
In his first start of the spring, Arizona right-hander Trevor Cahill allowed one run on two hits while striking out four in 3 1/3 innings.
Up next: The Brewers' biggest offseason acquisition will make his unofficial debut when Matt Garza starts against the Rockies in Scottsdale on Sunday. Garza's four-year, $50 million contract is the richest for a free agent in club history, and it gives the Brewers a trio of veterans (with Kyle Lohse and Yovani Gallardo) atop the pitching rotation. The game can be heard via Brewers.com webcast, with TV broadcaster Brian Anderson and radio broadcaster Joe Block teaming on the call.
Steve Gilbert is a reporter for MLB.com. Read his blog, Inside the D-backs, and follow him on Twitter @SteveGilbertMLB. This story was not subject to the approval of Major League Baseball or its clubs.