Campbell, who raised his batting average to .379, finished the night with three hits, two RBI and a walk. Infielder Derek Slate, a junior from Point Loma, was also two for four with a run.
Sam Brunner picked up the win for the Red Sox. He struck out one, walked none and surrendered one hit.
Over 700 fans were on hand at Currie Field to watch Campbell go deep and secure the Regina victory.
The Regina Red Sox now 22-14 visit Ross Wells Park in Moose Jaw Tuesday night against the Millers.