Kenley Jansen gets back into rhythm, and the Dodgers beat the Giants 2-1 in 10 innings

Clayton Kershaw affixed his eyes to a television inside the visitors clubhouse at AT&T Park. On the screen, the Dodgers clung to a one-run lead over the Giants. On the mound stood a pitcher who looked familiar, a boulder of a closer throwing cutters that touched 94 mph as they buzzed past San Francisco lumber.

“That was Kenley right there,” Kershaw said after Kenley Jansen struck out the side to secure his first save of the season in the Dodgers’ 2-1 victory in 10 innings. After 24 innings in two days in the Bay Area, the Dodgers escaped with a split and watched Jansen click into place.

The victory does not cure all that ails the Dodgers. The offense is more sickly than spry. The group stranded nine runners, a touch better than the 13 left aboard the day before. They wasted another quality outing from Kershaw. On Sunday they were rescued by a two-out run-scoring double from Kyle Farmer, the utility player who Jansen christened “What’s His Name” after the game.

The Dodgers finished this trip to Arizona and San Francisco with one victory and four defeats. At the very least, they flew back to Los Angeles with reason to exhale about their closer. Jansen fired cutters with improved velocity (93.1 mph on average, well above the 89-90 mph he showed last week) and a synchronized delivery. Jansen credited mechanical tinkering for his improvement.

“Finally I can sleep tonight,” Jansen said. “I’ll be honest and true with you. I feel great.”

Manager Dave Roberts felt something closer to relief. He declined to refer to Sunday’s game as a “must-win,” but acknowledged it wasn’t far off. The start by Kershaw only added to the necessity of securing a victory. Kershaw gave up one run in seven innings. He struck out six, but faded during his third time through San Francisco’s lineup. He has pitched three games this season and received two runs total from his teammates.

As two-way sensation Shohei Ohtani flirted with a perfect game in his home debut as an Angel, Kershaw polished a minor gem of his own. His outing lacked the exhilaration and the novelty of Ohtani’s performance. It ended in disgust, as Kershaw gave up two singles in the eighth before ceding the mound to J.T. Chargois. A single by San Francisco catcher Buster Posey tied the score.

The Dodgers mounted a rally in the 10th. Given the day off to recover from food poisoning, Cody Bellinger came off the bench with a leadoff double. Farmer stepped in with two outs against Giants reliever Pierce Johnson. Farmer stung a fastball off the right-field bricks to give the Dodgers the lead. The hit added to his highlight reel against the Giants; he recorded a walk-off against San Francisco in his big league debut last season.

“It was my opportunity to come and make the most of it,” Farmer said.

Roberts maintained a posture of serenity Sunday morning. His team had done little to alleviate his stress. The lineup swung without patience. They made contact without power. Before the game, Roberts sounded like an internist diagnosing various maladies affecting his hitters.

Yasiel Puig? Chasing too many inside fastballs.

Corey Seager? Lack of discipline within the strike zone.

Bellinger? Still trying to get his rhythm.

The offense remains either marooned at Camelback Ranch or paralyzed by the absence of All-Star leader Justin Turner. On Sunday they succumbed to the presence of Giants starter Ty Blach for the second time in nine games.

The fourth inning offered something productive, if still maddening. Puig led off with a bloop single. Enrique Hernandez walked. Blach tried another first-pitch changeup, this one to Matt Kemp. The pitch dove toward Kemp’s shins. He swung anyway, and dumped a single into right. Puig raced home, Kershaw had a lead and the Dodgers had the makings of a rally.

The threat did not last long. Blach tossed a 2-and-2 curveball over the plate. Logan Forsythe chopped into a double play.

“We’ve just got to find ways to get those big hits,” Kemp said.

Responsibility for the afternoon fell on Kershaw’s shoulders. He did not pitch beyond the sixth inning in either of his first two outings. He gave up a trio of home runs to left-handed hitters. His fastball velocity hovered closer to the upper-80s than the mid-90s. He looked solid, but not spectacular.

Sunday was different. From the outset, Kershaw commanded his curveball and carved up his hosts. At one point he retired 12 batters in a row.

An unlikely source slowed Kershaw. He gave up consecutive singles in the sixth. With one out he squared off with Joe Panik, who had taken him deep on opening day. Kershaw fired a slider on the inner half of the plate. Panik sliced it into right. Puig squinted through the sunlight to find the baseball. At the last moment he dove and snagged one out. Fooled by Puig’s read, Gorkys Hernandez went to third base. Puig flung the ball to second for a crucial double play.

As Kershaw went deeper, the outs got louder. Andrew McCutchen lined out to left to open the seventh. Evan Longoria roped another double, this one with two outs. Kershaw wriggled free when Pablo Sandoval chopped a 2-and-0 slider into the ground.

“I needed a few guys to bail me out today,” Kershaw said.

The eighth offered an uglier outcome. Kershaw hunched over at the waist after Hunter Pence singled. Kelby Tomlinson, a bespectacled utility player, laid down an immaculate bunt. The ball rolled beyond Kershaw’s reach and nestled into the grass between first and second. With Posey in the on-deck circle, called off the bench for his first at-bat of the game, Roberts opted for a right-handed reliever.

Roberts did not ask Jansen for a six-out save; three-out assignments have been enough of a challenge for Jansen this season. Roberts chose Chargois, a waiver-wire find who dazzled team officials during the spring. Posey tagged a 1-and-2 fastball for a score-tying single.

Chargois and left-handed reliever Tony Cingrani managed to avoid further damage. Farmer came through in extra innings. And for the first time this season, Jansen looked dominant.

“He’s a beast, man,” Kemp said. “We all know that. Two rough outings? Doesn’t matter. Long season: 170,000 games left. We’ve got to keep going.”

andy.mccullough@latimes.com

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