Here at Miller Park, though, the D-backs on Friday were using multiple sets even with no one on base. Turns out they've been doing that here since the 2011 National League Division Series.
"It was just a bad experience in the playoffs two years ago," Arizona catcher Miguel Montero said. "Ian [Kennedy] and [Daniel Hudson] made such great pitches and they just laid off them like they knew it was coming. So it was just like, huh, it made you think about it. If I'm hitting and I see that pitch and I don't know it was coming, there's 95 percent chance I'm swinging because it's too close to take and it's such a great pitcher's pitch."
When closer J.J. Putz came into the game in the ninth inning Friday, Montero was using only one sign, but that quickly changed during Jonathan Lucroy's at-bat.
"Last night when J.J. [in a] 1-2 count, he threw a splitter and we were using just one sign and Lucroy, it was a nasty split and he just spit on it like he knew it was coming," Montero said. "I was like, hmmm, so I went out there and we changed the sign and the next pitch, it was worse, and he swung at it. It's a little shady. I don't think we're the only team that does that here."
Montero, though, reiterated that he did not know for sure that the Brewers were somehow stealing signs, but that he was taking no chances.
"Just a precaution," Montero said. "Even if they don't do it, and I'm not saying that they do it."
Steve Gilbert is a reporter for MLB.com. Read his blog, Inside the D-backs, and follow him on Twitter @SteveGilbertMLB. This story was not subject to the approval of Major League Baseball or its clubs.