Selected 36th overall in the 2009 Draft, Miller (1-0) allowed one run on three hits and two walks after replacing the rehabbing Blake Hawksworth in the second frame of Class A Advanced Rancho Cucamonga's 4-2 victory over Inland Empire.
The 23-year-old left-hander had been at the Dodgers' extended spring training facility in Arizona after a groin pull forced him to miss the first six weeks of the campaign.
He last pitched competitively on July 30, allowing eight runs on four hits and five walks over one inning of the Double-A Chattanooga Lookouts' 15-4 loss to the Birmingham Barons. He was activated from the DL on Sunday and assigned to Los Angeles' California League affiliate.
Miller retired nine of the first 10 batters he faced before walking Carlos Ramirez to lead off the fifth. Justin Bass plated Ramirez with a two-out double to left field, but the Texas native finished strong, facing one above the minimum the rest of the way.
Last season the Baylor product went 7-8 with a 3.68 ERA in 25 games -- including 23 starts -- between Inland Empire and Double-A Chattanooga. He struck out 121 batters over 124 2/3 innings. Hawksworth allowed a run on a walk without a hit and one strikeout over his frame.