Dodgers’ Adrian Gonzalez won’t be switching back on his swing

SAN FRANCISCO — Adrian Gonzalez emerged as one of the finest power hitters in baseball during his final four seasons with the San Diego Padres.

He hit 30 home runs every year — and 40 one year — while playing in cavernous Petco Park.

His days as that kind of power hitter are gone.

BOX SCORE: San Francisco 4, Dodgers 3

That is not a whisper from an anonymous scout. That is the word from Gonzalez himself, who says he has been unable to recover the swing that made him an elite power hitter.

“I can still hit home runs,” Gonzalez said. “That is not going to be an issue. The full power is not the same.”

Gonzalez, 30, said he altered his swing when he injured his shoulder in 2010, his final season in San Diego. He had surgery after that season, then was traded to the Boston Red Sox.

“Last year, I tried to go back to the swing I had before I got hurt,” he said. “I tried it for the whole first half, with horrible results.”

He hit .283 with six home runs in the first half of last year, .312 with 12 homers in the second half. The Dodgers last August acquired Gonzalez, taking on a contract that guaranteed him $130 million through 2018.

He said he is most effective now with a flatter swing that generates more line drives, rather than an upward swing that produces more power. He is not a singles hitter by any means — he hit a career-high 47 doubles last season — but he says he is a better hitter against left-handed pitching and with runners in scoring position.

Gonzalez said he figures to lose about five to 10 home runs per season.

“I was a .280 hitter,” he said. “Now I’m more of a .300 hitter.”

Gonzalez is batting .337 this season, with three home runs and a team-high 22 runs batted in. He had a two-run, pinch-hit single Sunday against left-hander Jeremy Affeldt, whom the Giants summoned specifically to face him.

Gonzalez ran from first base to second on a subsequent single, then asked for a pinch runner because the running aggravated his strained trapezius muscle.

Gonzalez, who suffered the injury when he collided with an umpire Wednesday and has not started since then, is scheduled for an MRI examination Monday.

Short hops

Jerry Hairston Jr., who started in place of the injured Gonzalez on Friday and Saturday, did not start Sunday. He is hampered by a strained groin, but he declined to discuss it. A Dodgers spokesman said Hairston is not scheduled for an MRI examination. … With Gonzalez and Hairston unavailable, Juan Uribe made the first start of his career at first base. … The Dodgers plan to activate pitcher Chris Capuano to start Monday’s game. Infielder Mark Ellis, who has sat out the last eight games because of a strained quadriceps muscle, is expected to go on the disabled list. … Shortstop Hanley Ramirez, already on the disabled list because of a hamstring injury, is scheduled for an MRI examination Monday to determine the severity of and prognosis for the injury. … Manager Don Mattingly said rookie pitcher Matt Magill, who did not get through the second inning of his second major league start Saturday, would get another start. … The Giants never had back-to-back walk-off home runs against the Dodgers — not in California, not in New York, not anywhere — until Buster Posey and Guillermo Quiroz did the honors Friday and Saturday.

bill.shaikin@latimes.com

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