Bill Buckner hit a tie-breaking home run and Steve Crawford, making his first major league start in four years, held host Oakland to one run on four hits through 6 2/3 innings to lead Boston.
Buckner had three hits, including the two-run homer in the fourth inning, and scored twice. The homer was Buckner's fourth of the season and ended a 1-1 tie.
Crawford (3-2), normally a reliever, left the game in the seventh inning when he apparently hurt his elbow. He had retired 16 of 17 batters before leaving the game for Bob Stanley, who gave up a three-run homer to Dusty Baker with one out in the ninth inning. Bob Ojeda got the last two outs for his first save. Left-hander Bill Krueger (2-3) was the loser.
Oakland took to a 1-0 lead in the first inning on Carney Lansford's one-out single and Bruce Bochte's RBI double. Boston tied it in the second when Buckner singled with one out, went to second on Krueger's wild pitch and scored on Dave Stapleton's single.
Mike Easler doubled to lead off the Boston fourth, and Buckner followed with his second homer in two games. Wade Boggs' RBI single later in the inning gave the Red Sox a 4-1 lead.