Pinch hitter Chris Chambliss singled home two runs in the sixth inning to provide the winning runs in Atlanta.
With the score tied, 4-4, in the sixth, Dale Murphy led off with a single and went to third on Bob Horner's double that knocked out Mike Proly (1-2). One out later, Glenn Hubbard was intentionally walked to load the bases. After Bruce Benedict forced Murphy, Chambliss, batting for pitcher Donnie Moore, singled to center off reliever Bill Campbell to make Moore (1-0) the winner.
"I don't like coming off the bench, but I seem to do well when I do," said Chambliss, who was hitting only .227 at game time. "I don't believe in slumps. I'm just not hitting, but I'll just keep swinging until it happens."
The Braves then had to survive a ninth-inning scare when Scot Thompson got a pinch single and Bill Buckner, who homered earlier, hit a fly ball to right that Terry Harper caught at the wall.
The Braves had tied it at 4 in the fifth on an RBI single by Rafael Ramirez. That hit scored Benedict, who had doubled.
Chicago went ahead, 1-0, in the second off Pete Falcone as Leon Durham tripled and scored on a sacrifice fly by Keith Moreland. The Cubs made it 3-0 in the third inning on a two-run single by Durham and scored in the fifth on a solo home run by Buckner, his first of the year.