Moss' was a three-run shot off lefty Jeff Francis, his fourth of the spring. Reddick also got to Francis, hitting a solo shot in the fifth. He also collected an RBI single in the seventh.
A red-hot Derek Norris contributed with three hits and two RBIs, continuing a torrid spring. The A's backstop is batting .436 through 13 games, and his 12 RBIs are tied for the team high.
Francis went five innings for Cincinnati and was tagged for six runs total, allowing seven hits and three walks with five strikeouts.
For the A's, lefty Tommy Milone was responsible for three earned runs (four total) on five hits and a walk in five innings. He struck out two in his final Cactus League start and will next pitch in tandem with Dan Straily in the third game of the Bay Bridge Series on Saturday.
Brandon Phillips fired a solo shot off Milone in the first, and the Reds plated two more in the third on a sacrifice fly from Billy Hamilton and an RBI base hit off the bat of Todd Frazier. Hamilton drove another with a sacrifice fly in the fourth.
Up next: Minor Leaguer Murphy Smith gets the 12:05 p.m. PT start against the Angels at Phoenix Municipal Stadium in an exclusive webcast on Wednesday, the A's final Cactus League game at the storied ballpark. Righty Sonny Gray, meanwhile, will stay on schedule for his first career Opening Day start by pitching in a Minor League game.