Conor Gillaspie hit a two-run homer in the second inning, and Joe Panik added a two-run blast in the third. Another two-run shot came in the fourth inning from Jarrett Parker.
The Reds took a 4-2 lead with a four-run bottom of the second. Zach Vincej hit an RBI double off of Matt Moore, while Jose Peraza added an RBI infield hit and Dilson Herrera contributed a two-run double.
Moore pitched 1 1/3 innings with one earned run, one hit, two walks and three strikeouts. Reds starter -- and rotation candidate -- Tim Adleman gave up two earned runs on Gillaspie's homer, allowing four hits with two strikeouts over two innings.
Also vying for a spot in Cincinnati's rotation, Robert Stephenson was roughed up in the third inning for four earned runs on three hits -- including Panik's long homer to right field -- two walks and a hit batter.. San Francisco sent nine men to the plate that inning.
"I could give you plenty of reasons why it didn't go well, but the bottom line is I didn't make pitches. I'm not too happy with it, obviously," Stephenson said. "I really need to work on throwing the ball inside, and just had a hard time. A couple of times I got in there and, obviously, not for a strike, and at times where it counted, I missed over the plate and got hit hard."
Giants prospect Tyler Beede pitched two scoreless innings, allowing two hits and a walk. Reds pitching prospect Luis Castillo, acquired in last month's trade that sent Dan Straily to the Marlins, retired all six batters he faced in two innings with two strikeouts.
Giants up next: San Francisco will confront its cross-bay rival, the Oakland A's, who always pose a serious challenge, whether the sides meet in the regular season or Cactus League play. Giants right-hander Jeff Samardzija will oppose his A's counterpart, Sonny Gray, in Monday's 12:05 p.m. PT affair in Scottsdale, live on Gameday Audio.
Reds up next: Scott Feldman will make his Reds debut when he starts vs. the D-backs at 3:05 p.m. ET on Monday in Scottsdale, live on Gameday Audio. Rotation candidate Cody Reed will follow Feldman. Eugenio Suarez, who hit a home run on Saturday vs. Cleveland, is slated to be back in the lineup, along with Billy Hamilton.
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