SAN FRANCISCO -- It's a given that Matt Cain will keep striving to regain his winning form. Whether he's allowed to do that when his next turn in the Giants' pitching rotation arrives is another issue.
Manager Bruce Bochy indicated Tuesday night after San Francisco's 8-5 loss to the Chicago Cubs that he and the Giants' hierarchy will discuss the feasibility of starting Cain on Sunday against St. Louis, particularly in the wake of the right-hander's current lapses.
"We'll talk about Matty [Wednesday] and see where we are," Bochy said after Cain yielded six runs and eight hits in five innings to the Cubs, who settled matters early on Kyle Schwarber's three-run homer and Miguel Montero's two-run clout in the third and fourth innings, respectively.
Cain (2-4) has surrendered at least four earned runs in seven of his 10 starts this year, including five of his last six. He has allowed nine homers in his last eight outings, matching the total he allowed during the entire 2011 season.
"I just made a couple of bad pitches and they ended up costing us," Cain said.
Giants catcher Buster Posey implied opponents aren't missing Cain's mistakes. Citing Schwarber's homer, which landed squarely in the right-center-field stands, Posey said, "It seems like those pitches are being hit hard right now."
When somebody suggested to Cain that any improvement he makes will depend on adjusting, whether it's with his pitch selection or the mechanics of his delivery, he said, "That's kind of what this game comes down to. If you make big mistakes like that, hanging breaking balls to guys who can leave the yard, they're going to take advantage of you."
The Cubs apparently took advantage of a mechanical lapse on Cain's part to defeat the Giants for the fifth time in a row this year.
"It looked like his [arm] slot changed a little bit," Bochy said. "It got a little lower and his pitches flattened out a little bit."
The Giants have been willing to be patient with Cain, who underwent surgery to remove bone chips and spurs last August before he sustained a flexor tendon injury that delayed his 2015 regular-season debut until July 2. His three All-Star selections, combined with his postseason excellence in 2010 and 2012, earned him bottomless credibility with the franchise.
"I think it's fair to say that he's not quite where he's going to be," Bochy said. "We know what Matt's done for us and he's not there yet."
But the Giants cannot afford to let Cain struggle to overcome his pitching flaws during stretch-drive showdowns. Their fifth setback in six games left them 2 1/2 games behind the first-place Dodgers in the National League West. Cain's 6.15 ERA is his highest after 10 starts at any point in his Major League career.
Asked if he thinks he occasionally may have tried too hard to regain his winning form, Cain acknowledged, "I've been guilty of that. That's normal, being competitive. Any athlete is going to do that."