Rookie Will Clark's single provided the go-ahead run in the eighth inning, and rookie second baseman Rob Thompson threw out the Cubs' Shawon Dunston at the plate to finish the Giants' 2-1 victory and doubleheader sweep yesterday in San Francisco.

The Cubs, who also lost the opener by a 2-1 score, wasted good pitching by Rick Sutcliffe and Dennis Eckersley. The opener went 10 innings and ended with Chris Brown's sacrifice fly off Sutcliffe, who lost a four-hitter.

"We had five hours of great pitching," Cubs Manager Jim Frey said. "We had 18 chances to blow that second game open."

Dunston was the third runner the Giants threw out at the plate that game. With runners at first and second and two out in the ninth, Ryne Sandberg grounded to shortstop Jose Uribe. After Uribe's toss toward Thompson hit runner Terry Francona, Thompson retrieved the ball and caught Dunston trying to score.

"We've had guys thrown out at the plate a few times this year," Thompson said. "It was our turn to make those plays today."

In the opener, Sutcliffe (1-4) struck out nine in his first complete game since last June. Mike LaCoss (2-0) won a five-hitter and lowered his ERA to 1.71. Cardinals 3, Dodgers 1: St. Louis and Los Angeles had only eight hits between them, but the Cardinals' Mike LaValliere and Ozzie Smith got them when they counted most, singling runs home in the third inning against Orel Hershiser.

The Dodgers, who had won seven straight, had only three hits off Bob Forsch (2-1) and three relievers. Forsch doubled in the third inning and scored on two wild pitches by Hershiser (3-3). On the second one, catcher Mike Scioscia was partially blocked by umpire Eric Gregg.

Hershiser lost only three games last season. Pirates 5, Padres 2: Jim Morrison's two-out homer in San Diego started a three-run ninth-inning rally that extended Pittsburgh's winning streak to four games.

After the Padres had tied the game at 2-2 in the eighth, Morrison homered on an 0-1 pitch and shortstop Garry Templeton booted Sammy Khalifa's ground ball. After walks to Lee Mazzilli and R.J. Reynolds, Joe Orsulak singled to drive home two more runs.

Morrison had popped up twice and flied out in his previous at-bats. "I had three terrible at-bats," he said. "I knew I had to stay patient and not let down. I think I had a little help from Mother Nature. I didn't think that ball was going out, but the wind must have carried it."

The Padres stranded 10, twice leaving the bases loaded. Expos 7, Astros 6: Houston's first baseman, Glenn Davis, bobbled Al Newman's grounder in the ninth, allowing Andres Galarraga to score and win the game in Montreal.

Galarraga led off the ninth with a double off Dave Smith (0-1) and went to third on Tim Wallach's infield single. Newman then chopped a 2-2 pitch that Davis couldn't handle. The scratch hits helped negate Terry Puhl's third-inning grand slam. Phillies 5, Braves 1: In Philadelphia, Kevin Gross (2-3) pitched a four-hitter and Steve Jeltz's double drove in three runs. Gross struck out three and walked three. Atlanta's Joe Johnson (3-2) took the loss. Mets 7, Reds 2: New York's Darryl Strawberry hit two homers off Mario Soto (2-3) in Cincinnati. Soto, who allowed a league-high 30 homers last year, has given up 10 in six starts this season.

"It was a very ugly game," Mets Manager Dave Johnson said. "Very trying on a manager." He was particularly upset that starter and winner Ron Darling (2-0) walked six in 6 2/3 innings, although he gave up only four hits.

The Reds have lost eight straight overall and have lost 10 straight at home since winning their opener there. They haven't had worse luck at home in more than 27 years. Their player-manager, Pete Rose, got his first hit this season.