MILWAUKEE — The man in Section 118 does not have a press credential, a media day, or a podcast. He has a son, a cap, and, as of last Saturday, a story the entire state of Wisconsin now wants from him.

Garrett Mitchell hit the go-ahead home run in Game 4 of the National League Championship Series to send the Brewers to the World Series, per MLB.com, and the reporters who cover the team have now discovered the most reliable source in baseball: the father.

The narrator sat down — metaphorically, in a hallway, standing, with a father who kept looking at the field — with the elder Mitchell, who has an opinion about the swing and, like all fathers, an opinion about the swing’s history.

“People ask me when he was ready,” Mr. Mitchell said. “I’ll tell you. He was ready in the backyard. He was ready when he was nine and he pulled the ball into the neighbor’s tree and the neighbor’s wife came over and I said, ma’am, that boy is going to the Show, and she said the tree was a gift from her mother, and I said ma’am, my son is going to the Show, and we did not resolve the tree.”

Did he ever doubt it?

“Doubt is for people who have a second option,” Mr. Mitchell said. “I have one son. I watched him play every game in every weather in every town with a bad light. The doctors said his body. The doctors said his body a lot. I said, doctor, I have seen this boy play in the rain in a town whose name I can’t pronounce, and you’re telling me about his body? He played. That’s the whole report.”

The injury history is, in the specific, the whole story of Garrett Mitchell’s career: the center field he was built for, the bodies that kept him out of it, the season that finally let him stay in it. The father’s account of that history is a list of towns.

“There was a place in Arkansas,” he said. “There was a place where the bus broke down. There was a place where the trainer taped him so tight he couldn’t feel his fingers and he caught eleven fly balls and I counted every one from the fence. Eleven. I have the number. I have all the numbers.”

What did he say to his son before the at-bat?

Mr. Mitchell looked at the field for a long time.

“I didn’t say nothing,” he said. “That’s the part people don’t get. I didn’t say nothing. I’ve been saying it since he was nine in the backyard. The tree. The Show. You don’t say it twice. You just sit in Section 118 and you watch him do the thing I already know he can do, and when he does it, you don’t cheer. You exhale. There’s a difference. A cheer is for a surprise. An exhale is for an appointment.”

The Brewers open the World Series on Friday, October 23. The father will be in Section 118. The narrator asked him what he expects.

“I expect the same thing I expected in the backyard,” he said. “That boy is going to do it, and the neighbor’s wife is going to have to deal with the tree.”

He went back to watching the field.