Bryant, the Cubs' top prospect, did not start because of right shoulder fatigue. He took over as the designated hitter in the third inning, subbing for Anthony Rizzo, and crushed an opposite-field home run off the first pitch from Oakland starter Jesse Hahn. Bryant then launched a 2-2 pitch off Evan Scribener over the left-center-field wall leading off the sixth inning.
Bryant leads the Cubs with six spring home runs.
Bryant's first homer accounted for the only runs off Hahn, who struck out three in 3 1/3 innings in his second spring start.
"Just tip my cap to Bryant on that one," Hahn said. "He came off the bench cold, hadn't taken a swing all game, and I thought I located a good fastball down and away, and he just went out there and got it."
Kyle Hendricks, making his first spring start, retired all 15 batters he faced, throwing 54 pitches, 40 for strikes. The right-hander, projected as the Cubs' fourth starter, struck out three over five innings.
Hendricks, Joseph Ortiz and Jorge De Leon did not allow a hit or a walk over seven innings, and Matt Olson ended the perfect-game bid with a leadoff double in the A's eighth off Armando Rivero. Tyler Landendorf singled and Olson scored on Max Muncy's sacrifice fly.
A's Up Next: The A's will be back together as one unit Sunday after a split-squad trip to Las Vegas, and it will be right-hander Sonny Gray taking the mound for the second time this spring, meeting the Brewers at Maryvale at 1:05 p.m. PT, live on MLB.TV. Gray will be followed by veteran non-roster invitee Barry Zito. Gray allowed two earned runs on five hits in his two-inning Cactus League debut, and Zito has allowed four earned runs in 4 2/3 innings in one start and one relief appearance thus far.
Carrie Muskat is a reporter for MLB.com. She writes a blog, Muskat Ramblings, and you can follow her on Twitter @CarrieMuskat. This story was not subject to the approval of Major League Baseball or its clubs.