The Los Angeles first baseman also went deep in the second inning as the Dodgers stayed three games behind St. Louis in the race for the final National League wild card spot.
Shawn Tolleson (3-1) earned the win in relief of Clayton Kershaw, who came back from a hip injury to hold Cincinnati to one run over five full frames.
Brandon League secured the win with his fifth save.
Reds starter Homer Bailey (12-10) was tagged for five runs on five hits over 6 2/3 innings.
Denis Phipps socked his first major league homer for National League Central champs Cincinnati.