Doughtery (8-1) threw a complete game 5-hitter, striking out four and walking just one hitter.
Cumberland's only run came in the top of the second when Tyler Fisher doubled in Zach Diekmann, who had left off the inning with a double of his own.
Union pushed across single runs in the bottom of the first, the fifth, seventh and the eighth.
Matt Madigan (8-3) started for CU and took the loss. Madigan went 6.2 innings, scattering seven hits with five strikeouts and two walks. Lance McClain worked the final 1.1 innings giving up one hit, one earned run with two strikeouts and two walks.
Cumberland ends the season 46-21 overall after having won both the TranSouth Conference and Region XI tournaments.