BOSTON -- Mike Greenwell, forced to make his major league catching debut in the 10th inning, made a throwing error to ignite a seven-run outburst that powered the Oakland Athletics to a 11-6 triumph over the Boston Red Sox.
Terry Steinbach led off the 10th inning against loser Bob Stanley, 3-9, with a ground-rule double into the Red Sox bullpen. Alfredo Griffin bunted down the first-base line. Greenwell picked up the ball and his throw to first went over the head of second baseman Marty Barrett.
The A's added another run when Luis Polonia singled home Griffin. Mark McGwire gave the A's a 9-4 lead when he blasted a three-run homer, his 34th blast of the season, and Carney Lansford followed with his 10th homer. Steinbach capped the inning with an RBI single.
Greenwell started the game as the designated hitter, but moved behind the plate after the Red Sox pinch hit for catchers Marc Sullivan and Danny Sheaffer.
Boston cut the lead to 11-6 on RBI singles by Greenwell and Dave Henderson. Rookie Greg Cadaret pitched two-thirds of an inning to record the victory, his major league decision in four appearances.
The Red Sox had tied the score 4-4 with three runs in the ninth. Mike Greenwell led off with a walk off Jay Howell, Dwight Evans doubled to center and Bill Buckner walked. Pinch hitter Don Baylor lifted a sacrifice fly to score Greenwell. After Ed Romero, who pinch hit for Sheaffer, struck out, Ellis Burks tripled home Evans and Buckner.
The A's had gone ahead 3-1 with three runs in the sixth. Polonia lined a one-out single and Tony Bernazard walked. Jose Canseco followed with a single off the top of the left-field wall, scoring Polonia. After McGwire bounced out, Lansford tripled to left-center, scoring Bernazard and Canseco to make it 3-1.
Oakland added a run in the seventh on Griffin's sacrifice fly.
The Red Sox had taken a 1-0 lead in the fourth. With one out, Wade Boggs doubled and scored on Jim Rice's single.
The victory improved Oakland's record to 7-3 against the Red Sox this season, assuring the A's of their first season-series triumph over Boston since 1976.