"He was a little off, I think that's fair to say," Giants manager Bruce Bochy said.
Overall, the Giants endured a discouraging start to their two-city visit here and St. Louis, where the National League Central's leaders are based. They mustered four hits in 7 2/3 innings against Brewers starter Yovani Gallardo, who could join Cain on the NL All-Star team. The Giants have lost 15 of their last 18 games at Miller Park, including five in a row.
Another victory probably would have guaranteed Cain's hotel reservation in St. Louis for the July 14 Midsummer Classic. He entered Friday riding the crest of success, recording a 1.89 ERA in a nine-start span that encompassed his winning streak.
Naturally, Cain (9-2) hungered to thrive even more.
"You want to keep winning. You want to keep doing well for your team," he said. But, as a result of the defeat, he added, "You feel like you let them down."
After Pablo Sandoval gave the Giants a brief lead with a two-out, first-inning home run off Gallardo. Milwaukee responded in its half of the inning with Craig Counsell's leadoff triple -- a slicing line drive that scooted under left fielder Randy Winn's glove -- and RBI doubles by Ryan Braun and Casey McGehee.
Both Braun, who mashed a curveball, and McGehee connected with the first pitch they saw from Cain.
"They kind of jumped on me a little bit," Cain said. "I didn't get a chance to go at Braun. I was just trying to throw a curveball in there to get a strike and I probably left it more over the plate than I wanted to. I was trying to freeze him to get ahead."
McGehee and Cain were facing each other for the first time.
"You think guys who haven't seen you might take [a pitch or two] to see what it looks like. But he didn't," Cain said.
Don't interpret Cain's explanations as excuses.
"I knew these guys were going to be real aggressive, but I thought if I made quality pitches they'd get themselves out. They didn't," he said.
J.J. Hardy lengthened Milwaukee's lead to 3-1 with his seventh home run of the season, a one-out drive to center in the third inning.
Then came Milwaukee's two-run fifth, when the Giants' remaining hopes dissolved. Cain began the inning by walking Gallardo and Counsell. Hardy laid down a bunt that third baseman Pablo Sandoval and Cain approached before the latter, after hesitating briefly, pounced on the ball but threw wide and late to first base. The play was ruled a single and loaded the bases. Braun then singled home a run and Prince Fielder lifted a sacrifice fly.
Cain was unsparing in his self-criticism.
"I beat myself in the fifth by walking guys. There's no way around it," he said. He repeated that he "beat himself" by not handling Hardy's bunt properly. "As a pitcher," Cain said, "you have to make the assumption that you're fielding it no matter what until it happens or you get called off."
Gallardo (8-4) weathered his trouble more smoothly. He struck out Matt Downs and retired Cain on a grounder to strand Giants on second and third in the second inning, then coaxed Downs' harmless fly to maroon two more runners in the seventh.
Both times, Nate Schierholtz was on base. He went 2-for-4, improving to 7-for-13 during a three-game stretch. Schierholtz appears to be on the brink of claiming steady activity, if not a regular role, but the evening's outcome left him reluctant to address this possibility.
"If we don't win, it's not satisfying, no matter how well you do," he said.