Eaton surrendered four runs to Milwaukee in the first inning and six overall in 4 1/3 frames, ballooning his ERA to 6.09, the highest in the National League and the third highest in the Majors.
"It's 'What is it? What is it?' as opposed to, 'It's this," Eaton said after Sunday's 8-6, 11-inning victory, admitting that an answer to his struggles has been hard to pinpoint. "I feel good going into the innings. Coming out of the innings, I'm frustrated."
Eaton endured a rough first seven starts as a Phillie, compiling a 7.43 ERA. The struggles subsided for his next seven outings -- from May 15 through June 17, he posted a 3.29 ERA -- then resumed in his next nine outings. In this period, the right-hander has posted one quality start, and none in his past six.
The Brewers got to Eaton for four runs in the first, raising his first-inning ERA to 7.63. It improves to 5.25 in his other innings. Eaton has allowed 19 runs in the opening frame, 23 in the second.
Phillies manager Charlie Manuel said Eaton's command is the issue, and the right-hander, well, he's not really sure.
"Maybe it's that I don't have the attitude right off the bat," Eaton said. "Maybe [I] just [need to] get after it in the first inning, then settle in. I don't know if that's right or not. I'm thinking out loud to you guys [in the media]."
The last Phillies pitcher to post a league-high ERA was Mark Leiter, who registered a 5.67 ERA and went 10-17 in 1997. Eaton hopes to figure it out before he replicates that.
Ken Mandel is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.