Johnny Cueto widened his eyes, pursed his lips and shook his head.
“I don’t know,” he said through an interpreter. “I don’t know what happened.”
Cueto was referring to the fifth inning Tuesday night, in which his trademark command seemed to desert him and he allowed four runs that were the difference in the Giants’ 4-3 loss to the Arizona Diamondbacks.
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But explanations are proving elusive to the Giants in general right now. Two days after a record-setting offensive performance and their first series win at home since the All-Star break, the Giants could sustain no momentum against a Diamondbacks team that entered Tuesday’s game in last place and their ace, Zack Greinke getting the start.
The loss ensured the Giants will go into September without a three-game winning streak in the second half. It also dropped them two games behind the Dodgers, who were rained out in Colorado. They will try to split the two-game series behind Matt Moore on Wednesday afternoon before flying to Chicago for four games against the streaking Cubs.
Among the many illustrations of the Giants’ second-half struggles is they are 8-18 in games started by the top three members of their rotation. Cueto failed to complete five innings for the first time in a Giants uniform Tuesday despite not allowing a hit over the first three.
Cueto toppled in the fifth, beginning when he issued the first of three walks in the inning to Yasmany Thomas. Chris Owings then tripled to tie the score at 1-1.
Cueto walked Greinke, Jean Segura singled to drive in Owings and A.J. Pollock walked two batters later to load the bases. Cueto made a good pitch to strike out cleanup hitter Paul Goldschmidt, but Welington Castillo hit a two-run single, giving Arizona a 4-1 lead.
“I tried to get out of the inning, I tried to make my pitch,” Cueto said through interpreter Erwin Higueros. “I really don’t know what happened. I didn’t do my job.”
“We got behind in some counts, I think that was the main thing,” catcher Buster Posey said. “Castillo put a pretty good swing on a tough pitch.”
It was the 36th and final pitch of the inning for Cueto, who has one win over his last nine starts.
“Once he got to that pitch count, that many pitches in the last two innings, I felt like I had to go get him,” manager Bruce Bochy said. “It’s unfortunate because he was really throwing the ball well and it just got away from him.”
Cueto’s record wasn’t the only casualty Tuesday night. Reliever Sergio Romo seemed to tweak his right knee covering first base in the ninth inning, though Bochy said after the game Romo is “fine” and should be available Wednesday. Center fielder Denard Span left the game after the sixth inning with neck stiffness, which Bochy said Span has dealt with before.
“With this neck thing that’s come up before, I think in Arizona, it’s got to be a little concern,” Bochy said. “But our hope is he’ll show up tomorrow and he’ll be fine.”
Angel Pagan took a leisurely pace into second base on a seventh-inning double that might have been a triple when Pollock had trouble picking the ball up in center. Bochy said Pagan’s hamstring was “a little tight.”
“He was being a little cautious with it,” Bochy said. “The last thing I guess we need to lose is him right now as well as he’s playing.”
A Giants offense that scored 13 runs in its finale against the Braves met a familiar foe in Greinke, who improved to 4-0 with a 1.66 ERA in six career starts at AT&T Park and 9-1 with a 2.35 in his career against the Giants. Greinke looked vulnerable early Tuesday, throwing 70 pitches in the first three innings, but held the Giants to two runs in six innings.
Against an Arizona bullpen with the N.L.’s highest ERA, the Giants hit into rally-killing double plays in the seventh and eighth innings. Diamondbacks closer Daniel Hudson hit Jarrett Parker with two outs in the ninth and gave up an RBI single to Pagan, but got Posey to hit a hard grounder to Segura at second to end the game.
“We created those chances out there that we couldn’t cash in on,” Bochy said. “That’s what you try to do in the game is get runners on. That big hit was eluding us.”
Posey was asked if the Giants’ lack of consistency is a concern going into September.
“No, I mean you just come out and play the next game,” he said. “I’m sure you get tired of hearing that. But we get tired of hearing about the questions too sometimes.”