Maldonado finished 2-for-3 with five RBIs. Albert Pujols and Nolan Fontana drove in one run apiece for the Halos, while Ben Revere added two doubles, including a two-run shot in the eighth, and Sherman Johnson doubled in the eighth.
Jaff Decker, who is battling for Oakland's fifth outfield spot, went 1-for-2 with a double and a walk. The A's were held scoreless until Brett Vertigan got them on the board with an RBI single in the ninth.
A's starter Logan Shore, the club's 2016 second-round Draft pick, allowed one run on two hits while striking out three and walking one over four innings.