Eric Davis led off the bottom of the 11th inning with a home run yesterday at Riverfront Stadium, becoming the seventh player in major league history to hit 30 home runs and steal 30 bases in one season and giving the Cincinnati Reds a 5-4 victory over the San Francisco Giants. The win stretched the Reds' lead in the National League West over the second-place Giants to three games.

Davis, 25, in his third major league season, hit his 30th homer on a 2-1 pitch from Jeff Robinson (6-7), the fourth San Francisco pitcher. Davis stole two bases to raise his season total to 39.

He joins Willie Mays (1956, 1957), Hank Aaron (1963), Bobby Bonds (1969, 1973) and Dale Murphy (1983) in the National League and Bonds (1975, 1977, 1978), Tommy Harper (1970) and Ken Williams (1922) in the American League as the only players in the so-called "30-30" club.

"I'm not too concerned about that," Davis said of the accomplishment. "I was just looking to hit the ball somewhere and get on and score a run. I knew he was going to give me a pitch to hit."

Davis' homer gave rookie Jeff Montgomery (1-0) his first major league victory.

Cardinals 9, Pirates 1:

Joe Magrane pitched an 11-hit complete game in 103-degree heat in St. Louis and Jim Lindeman and Terry Pendleton hit home runs as St. Louis swept its three-game series with Pittsburgh and increased its lead in the East to six games. The Cardinals had lost seven straight games before the Pirates came to town. Now, the Pirates have dropped seven in a row.

Five of the St. Louis hits off Hipolito Pena (0-3), making his first start of the season, were for extra bases as Magrane (6-2) won for the first time in his last seven starts.

Mets 7, Expos 4:

Ron Darling and Roger McDowell combined on a four-hitter and Keith Hernandez drove in New York's first three runs in Montreal. The Mets came within one-half game of the second-place Expos in the East.

Darling (7-7) gave up two singles in 6 2/3 innings but walked eight. McDowell allowed a two-run single to Tim Wallach in the seventh after Darling walked the bases loaded for the second time in the game, but McDowell recovered to earn his 16th save.

Cubs 3, Phillies 2:

Ryne Sandberg's single over a pulled-in outfield in the 10th inning gave Chicago, at home, its second straight win over Philadelphia. Manny Trillo tied it with two out in the ninth with his eighth homer of the season.

Braves 10, Dodgers 5:

Paul Runge's second major league homer keyed a six-run fourth inning that also included a three-run double by Ted Simmons as Atlanta won at home.

Dodgers first baseman Franklin Stubbs dislocated his right shoulder and was placed on the 21-day disabled list.

Astros 6, Padres 0:

Houston's Mike Scott won his 12th game of the season and increased his Astrodome record over San Diego to 9-0. Cleanup man Alan Ashby homered, doubled and singled and drove in three runs.