SAN FRANCISCO -- Sandy Alcantara feels comfortable being a workhorse.

For most of Friday night’s game against the Giants, Alcantara appeared bent on duplicating the four-hit shutout that he pitched in his last start against Kansas City. But the Marlins couldn’t score for Alcantara, who worked seven effective innings in the Marlins’ 1-0 loss at Oracle Park. It was Miami’s 22nd shutout defeat of the season.

• Box score

Alcantara (5-13) rated his stuff as “so-so,” which might make observers wonder how he performs when he feels sharp. Though he matched a season high by allowing nine hits, he walked none for the first time since his initial regular-season start. The right-hander remained among the National League rookie leaders in strikeouts by fanning six, increasing his total to 137. He has worked at least seven innings in six of his last seven starts. That stretch has increased his overall total to 178 2/3 innings, which leads all rookies.

“From start to finish, he has been getting better all the time,” Marlins manager Don Mattingly said.

The Giants probably would remark, “Amen.” Alcantara possesses a 1.32 ERA in three career starts against them. But San Francisco did enough to secure its fifth 1-0 triumph of the year. Miami mustered four hits, all singles, and moved no runners into scoring position as Tyler Beede (5-9) and two relievers silenced the Marlins.

Alcantara blanked the Giants until the sixth inning, when Stephen Vogt doubled off the base of the right-field wall, advanced to third on Kevin Pillar’s groundout and scored on Buster Posey’s bouncing single through the infield’s left side.

The Marlins absorbed their seventh defeat in eight games. Entering this game, they had compiled a 20-11 record at San Francisco since 2010.

Cooper injured

Marlins right fielder Garrett Cooper left the game with a bruised left knee after making a lunging catch of a shallow line drive hit by Mike Yastrzemski, San Francisco’s first batter of the game. Harold Ramirez replaced Cooper.

Cooper’s playing status was rated as day to day. An examination revealed no structural damage in the knee, which he obviously found encouraging. He was able to walk with no apparent trouble, though he said that his leg felt “pretty tight” behind his knee.

“We’ll see how I wake up and feel,” said Cooper, who was on the injured list for the season’s first month with a strained left calf.

Cooper didn’t waste time lamenting his misfortune.

“It’s baseball,” he said. “You can’t get frustrated over things you can’t control.”