Matt Duffy and Justin Maxwell each had a homer against Angels' starter C.J. Wilson, who allowed three hits over 4 1/3 innings, walked four and struck out two.
Scratched from two previous scheduled starts, Wilson has a 1.32 ERA over his last 34 innings.
"I just polish what I'm good at and work on the things I'm not,'' Wilson said. ``My mechanics are good and my delivery is positive but there's no correlation to location just yet.''
C.J. Cron doubled home a run and Efren Navarro hit an RBI single against Giants reliever Jeremy Affeldt in the top of the eighth.
Sergio Romo made his third appearance, recording two outs in the ninth.
Bumgarner struck out five and did not walk a batter. Gregor Blanco, who had two hits and a stolen base, made a diving catch in the sixth to help Bumgarner.
"Our guys are going to play hard no matter what the time of year,'' Bumgarner said. ``I know what those guys can do and I'm 100 percent comfortable with them out there.''
Drew Rucinski pitched 4 2/3 scoreless innings, striking out five, to earn the win for the Angels.
Bumgarner, the 2014 World Series MVP, received a standing ovation after flying out deep to center field in the fifth inning.
"It was an out, I didn't do anything,'' Bumgarner said. "I swing at strikes. I try to, anyway.''
Wilson said he threw a fastball down the middle of the plate.
"I like hitting,'' Wilson said. ``I was chapped I wasn't able to hit. Afterward I was `oh, too bad.' He was laughing. I didn't get to hit, so that's the karma.''
Angels: Wilson hopes to get the most of his next bullpen session as he strives to build arm strength and his pitch count before the season opens.
"Instead of throwing what I call a cardio bullpen, where I'm throwing as hard and as fast as I can to wear myself out, I'll do a more thoughtful one,'' Wilson said. ``Maybe take a camera out there, pause after 10 pitches and think about it. Spring training is great because you're facing guys you don't normally see.''
Giants: The only hit Bumgarner allowed was on a changeup.
"It was a good pitch,'' Bumgarner said. ``He stayed on it and hit it good. Regardless of the results, it's just about getting ready for the season. I feel close. Everything has felt good the last few times and all my pitches are feeling good. My secondary pitches are better than they usually are at this point.''
Angels: OF Matt Joyce (right hamstring) could return to the lineup Tuesday. He hasn't played in just over a week. RHP Garrett Richards (left knee) is expected to pitch in a minor league game Monday.
Giants: OF Angel Pagan (back stiffness) took part in some baseball-related activities and could play Tuesday. C Andrew Susac (right wrist) appeared in his first game in 11 days, throwing out Mike Trout on a steal attempt and picking another runner off third base.
Angels: RHP Matt Shoemaker pitches for the Angels when they host the Seattle Mariners in Tempe on Monday.
Giants: The Giants have not announced a starter for Monday's home game against the Kansas City Royals, although it is RHP Jake Peavy's turn after he threw five innings in a minor league game on Wednesday.
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