Pitcher Scott Sanderson made his first major league home run a grand slam for the last four runs of a six-run Montreal third inning in Chicago's Wrigley Field.

NL batting leader Al Oliver led off that rally with his 21st homer and after Chicago chipped a 7-1 deficit to 7-6, Oliver provided Expo breathing room with a two-run double in a three-run eighth.

All told, 14 Montreal hits backed Sanderson (10-11), who equaled a career high with 10 strikeouts (in 6 2/3 innings) and Woodie Fryman, who pitched his 11th save. Ryne Sandberg plagued Sanderson with a double- two-run homer and an RBI triple that brought on Fryman.

After Oliver led off the third by breaking a 1-1 tie, Gary Carter singled off Randy Martz (9-9), went to second as Tim Wallach was hit by a pitch and scored on Chris Speier's single. Doug Flynn's single loaded the bases and Sanderson hit a 1-1 pitch into the right field bleachers.

Sanderson was quick to admit "I didn't hit it good, the wind (14 mph) had something to do with it."

Perhaps, but nobody could deny the emotion involved. "Both my mother and dad were out here and saw it," said Sanderson, who grew up in suburban Northbrook, Ill.

"Sanderson pitched good," said Manager Jim Fanning, "except for a couple of innings after hitting that homer. Emotionally, he had to shove it back in his mind. It was a great feat . . ."