After his team played 20 games in 20 days before finally getting a day off, a subdued Dodgers Manager Joe Torre admitted he felt "flat" when he arrived at Chase Field to start a three-game series with the Arizona Diamondbacks.
Kershaw, who had a 5-1 record and 1.06 earned-run average in his prior 11 starts, was tagged for four runs in the inning to give Arizona a 4-1 win in front of 31,573.
"It was a bad inning, I could have controlled the damage a lot better than I did," Kershaw said.
The teams also tagged each other in an apparent game of brushback pitches.
After Matt Kemp hit a home run in the fifth inning for the Dodgers' lone run, Dan Haren (12-7) threw inside to Kemp twice in the seventh inning before walking him.
In the bottom of the inning, Dodgers reliever Ronald Belisario hit Arizona's Mark Reynolds. Then, in the eighth inning, Haren hit Andre Ethier between the shoulder blades as Ethier turned to avoid the pitch.
As Ethier slowly walked to first base, home-plate umpire Jerry Layne escorted him and then appeared to give Haren a warning.
After the game, Ethier was asked what Layne said as he walked to first. "Oh, nothing, he said, 'Just take your base,' " Ethier said.
But did Ethier think it was retaliation? "Of course, I think it is," he said. "But you never know."
Haren, he said, "seemed to be pitching pretty well tonight."
Despite the one rough inning, Kershaw (8-7) showed traces of his recent success, striking out nine Diamondbacks before leaving after 4 1/3 innings.
"The kid battled," Torre said. "He was throwing some strikes. He didn't do a good enough job with two strikes" on the batters. "He really struggled in that second inning."
The Dodgers -- who went a lackluster 8-12 in that 20-game stretch -- saw their record drop to 13-15 since the All-Star break as their NL West lead remained at six games over Colorado and 6 1/2 over San Francisco, who both lost.
They mounted only six hits against Haren -- three by Manny Ramirez -- through Haren's eight innings.
Kershaw's forgettable second inning opened with a walk to Reynolds, who scored on Miguel Montero's double.
Rusty Ryal walked, Trent Oeltjen singled and Augie Ojeda hit a slow grounder that forced Oeltjen at second base but allowed Montero to score.
Haren helped his own cause by lining a single to drive in Ryal, and Kershaw then threw two wild pitches to the same hitter, Stephen Drew, the second of which let Ojeda score.
"I couldn't really put the ball where I wanted to," Kershaw said. "I didn't have great control."
One bright spot for the Dodgers was Ramirez, who had two singles and a double against Haren. Ramirez has always hit Haren well, having batted .500 against him entering the game.
Ramirez's double off the left-field wall came with one out in the sixth inning and he moved to third on Casey Blake's single. But James Loney grounded into a double play.
The Dodgers also threatened in the ninth inning with men at second and third with one out, but Orlando Hudson struck out and pinch-hitter Mark Loretta flied out.