It worked. Arrieta held the Cardinals to three hits over seven scoreless innings and picked up the win in the Cubs' 2-0 victory.
"Some guys need a pat on the back and some guys need to be yelled at, and I'm one of those guys who likes to be yelled at," Arrieta said. "[Montero] recognizes things in situations that I need to do differently, and it's great to have a voice like that behind the plate. We worked very well together."
At first, Montero said they had a "chat." But he admitted to using a more forceful tone.
"My job is to learn every personality," Montero said. "I'm like a psychologist as well. I had a really good impression of him, a really good read of him. I know he's a guy who you can go a little bit hard on him and he can take it and he'll get better. Some guys, you have to go softer because you don't want to hurt their feelings. I went to the mound, I know he can take it, and I let him know what I think. It did help, because he agreed with what I said."
Arrieta switched from trying to perfectly place pitches on the corners to becoming a power pitcher.
"You could probably hear the snap of the glove throughout the ballpark," Cubs manager Joe Maddon said.
After he came out in the seventh, Arrieta got a hug from teammate Jon Lester, who took the loss Sunday in the season opener. Lester posted on Twitter: "Certainly not how you draw it up, but the atmosphere was awesome last night, and I know @JArrieta34 is gonna pick me up tmrw! #NVRQT #LetsGo"
Arrieta's response: "That's what we do brother, watched you do it for years. @Cubs"
"It's a mutual admiration for each other, as well as the rest of the guys we have here," Arrieta said. "I think that has to come first before you win, and the quicker we can all get on that page and pick each other up, the better off we'll be."
If pitching doesn't work for Arrieta, Maddon had a suggestion.
"This guy should do the next kind of Jane Fonda workout video on the male side of things -- put his leggings on," Maddon said. "This guy's workout is incredible. He deserves everything he's got. I saw him in Baltimore, I'm seeing him now, and he's definitely matured as a Major League pitcher. This guy is really good."