Votto's first home run of the spring came off A's starter Sonny Gray. Billy Hamilton had two hits for the Reds, including a push bunt down the first base line that caught pitcher Josh Lindblom flat-footed. Lindblom couldn't get to first base to cover on the play.
Hamilton stole second and third as Lindblom fell behind in the count to Phillips, who belted his second home run. Hamilton also singled home a run in the second.
''Billy is that guy. He's doing the things we've asked him to do,'' Reds manager Bryan Price said. ''We've asked him to get on base and make things happen. He's been terrific. He's done everything we've asked for and more.''
On defense, Hamilton made a diving catch in center field of a line drive hit by Alden Carrithers.
Derek Norris, one of three catchers in the running for roster spots with the A's, doubled home two runs in the first off Tony Cingrani. That came after Norris' foul pop fell between Votto and catcher Devin Mesoraco, who was charged with an error.
''It wasn't a great game but it was nice to win,'' Price said.
Oakland designated hitter Yoenis Cespedes was 0 for 2 with a walk, dropping his batting average to .111.
A's third baseman Josh Donaldson left in the middle of the fourth with a minor sprain in his right calf, according to manager Bob Melvin.
Athletics: Gray pitched three-plus innings after throwing four in his previous outing. He gave up five runs, three earned, and six hits.
Consecutive singles by Todd Frazier, Zack Cozart and Skip Schumaker to open the fourth led to Gray's early exit.
''I felt I didn't throw enough strikes,'' said Gray, who walked two and struck out four. ''I was nibbling all around. I was trying to treat this like a regular game. I threw a lot of pitches, 69, around the zone, just not in it.''
Reds: Cingrani pitched into the fifth but left with none out. He was charged with five runs - three earned - and three hits. He struck out four, walked three and balked, which allowed another run to score. Oakland's Billy Burns struck out swinging but reached base on a wild pitch.
''I was overstriding in the first inning,'' Cingrani said. ''I found my mechanics, though. In the fifth my arm was dead. Maybe it was because we had a long fourth.''
Athletics: Outfielder Craig Gentry has been held out with a strained lower back. He has been sidelined since the first day of workouts. Gentry is scheduled to take batting practice Sunday. ... Right-handed starter A.J. Griffin has a strained right arm. He has had discomfort all spring, and the A's finally shut him down for three weeks of rest. An MRI revealed no damage. ... Right-hander Jarrod Parker is scheduled to consult with Dr. James Andrews on Monday to determine the cause of tightness in his right forearm.
Reds: Right-handers Mat Latos and Jonathan Broxton have completed their throwing programs and are scheduled to participate in game action early this week. ... Sean Marshall began his throwing program Friday with a pain-free, 20-pitch bullpen session. He is scheduled to play long toss Sunday. ''Marshall has a little bit of work to do,'' Price said.
Gray and Cincinnati pitchers Nick Christiani and Drew Hayes were on the same team at Vanderbilt for one year. Christiani was drafted by the Reds in 2009. Hayes was picked in 2010. Oakland chose Gray in the first round in 2011. Mike Minor was a teammate as well, drafted in the first round by Atlanta in 2009.
A's outfielder Sam Fuld scored his 10th run against the Reds. He came into the game second in the Cactus League with nine. Fuld has been in 14 games and played all three outfield positions. He has appeared in 10 games in left, six in center and one in right - shifting from one spot to another in some games.
A's shortstop Jed Lowrie singled to extend his hitting streak to seven games.