LOS ANGELES — For five innings on Saturday night, Yoshinobu Yamamoto looked every bit like the ace the Dodgers have leaned on throughout the first half of the season.
Then, one inning changed everything.
Yamamoto unraveled in a disastrous sixth inning, the offense continued its recent slump, and the Dodgers dropped their series to the Arizona Diamondbacks with a 9-2 loss at Dodger Stadium, falling to 61-35 with one game remaining before the All-Star break.
Locked in a scoreless duel with Brandon Pfaadt through four innings, Yamamoto appeared to be in complete command despite surrendering an RBI fielder's choice to Tim Tawa in the fifth that gave Arizona a 1-0 lead.
But the sixth inning quickly spiraled.
William Liang-Imagn Images
Los Angeles Dodgers pitcher Yoshinobu Yamamoto (18) throws during the second inning against the Arizona Diamondbacks at Dodger Stadium.
A leadoff walk opened the door for the Diamondbacks, and they capitalized on every mistake. Max Kepler extended the lead with a sacrifice fly before James McCann delivered the knockout blow, crushing a three-run homer to left field as Arizona erupted for five runs in the inning.
For Yamamoto, the inning was as frustrating as it was costly.
"I gave up a walk as a leadoff and as a result, it started everything," Yamamoto said.
His final line reflected one of his toughest outings of the season: six innings, five hits, six earned runs, four walks and six strikeouts on 103 pitches. The loss dropped him to 9-6 while his ERA climbed from 2.49 to 2.85.
Despite the ugly final numbers, Yamamoto's outing served as another reminder of how thin the margin for error has become when the Dodgers' offense isn't producing. One inning erased what had been another quality performance.
The Dodgers' bats offered little support.
The Diamondbacks kept the Dodgers quiet for much of the evening before the Dodgers finally broke through in the sixth. Andy Pages lined an RBI single to score Tommy Edman before Mookie Betts followed with an RBI single of his own after Freddie Freeman kept the inning alive with a base hit.
That would be all the offense the Dodgers could muster.
The lack of timely hitting has become an alarming trend heading into the break.
"Not really, just baseball," Teoscar Hernández said when asked if there was concern about the recent offensive struggles. "Just not doing what we supposed to do, and not hitting when we have to hit. Missing a lot of situations with men in scoring positions. That's when we are so good, when we make long innings."
Dave Roberts echoed the urgency as the Dodgers try to avoid carrying negative momentum into the second half.
"We have to find a way to win a game tomorrow and feel somewhat better going into the break," Roberts said.
Things didn't improve after Yamamoto exited.
Landon Knack made his first appearance of the season out of the bullpen and struggled to find the strike zone. After hitting Geraldo Perdomo and issuing consecutive walks to Corbin Carroll and Gabriel Moreno, Arizona added another run on Kepler's second sacrifice fly of the night.
The Diamondbacks kept pouring it on in the eighth and ninth. Nolan Arenado launched a solo homer before McCann struck again, blasting his second home run of the game to cap Arizona's 9-2 victory.
Knack ultimately logged the final three innings, allowing four hits, three runs, two walks and striking out two on 60 pitches.
The defeat secured a series loss for the Dodgers and continued an uncharacteristic stretch in which both the pitching and offense have struggled to click together.
Still, with a 61-35 record entering Sunday's first-half finale, the Dodgers remain in a strong position. But after watching Yamamoto's lone mistake-filled inning snowball into another lopsided defeat, they'll head into the break searching for cleaner baseball and more consistent offense.
The Dodgers will try to salvage the finale Sunday afternoon behind Emmet Sheehan, while the Diamondbacks will send Mitch Bratt to the mound before both clubs head into the All-Star break.