Research for my next book, about the Oakland A’s dynasty of the 1970s, to be published by Houghton Mifflin in 2015, has turned up boundless examples of unwritten rules from that bygone era. The latest, from Oakland Tribune beat writer Ron Bergman,  July 10, 1972: 

Jim Longborg threw a pitch in the first inning that bounced in back of Reggie Jackson. Blue Moon Odom retaliated by throwing behind Dave May, the first batter in the Milwaukee second. The ball nicked him in the back.

On the way to first, May exchanged words with Odom. Later in the inning, with May on third, Odom picked up Rick Auerbach’s attempted squeeze bunt and ran down May. A few more words were heard.

“Odom was saying that he didn’t think he hit May,” said plate umpire Don Denkinger. “At that point, I said if anything more happened, I’d have to warn both managers.”

Jackson said he thought Longborg was throwing behind him deliberately, and added, “It’s no fun, a pitch like that. It pleased me what Odom did. We like to play behind a guy like that.”

Longborg said he wasn’t throwing behind Jackson deliberately. Odom wouldn’t say that.

“That pitch didn’t get away from him that much,” Moon said. “He’s got pretty good control. It was intentional. They asked me why I threw behind May. I told them to ask their pitcher. It didn’t matter who’d been up first the next inning — my mother, or the manager — I still would’ve thrown at him. I meant to throw behind him. I didn’t try to hit him. I didn’t think I hit him until [A’s catcher Dave] Duncan told me later that I ticked his shirt. I told [Brewers first baseman] George Scott that I would’ve thrown at him if he’d been the first up. And he’s one of my big buddies.”

Over in the Milwaukee clubhouse, Scott shook his head from side to side.

“Man throw behind you, you got to throw at somebody else,” Scott said. “I’m glad I wasn’t the first one up.”

May walked in from the shower and said that “I definitely will remember this. It will stick in my mind. Lonborg wasn’t throwing at Jackson. I told Odom after he threw at me that I was coming out to get him. I went out to see what he was going to say. He didn’t have anything to say. When a guy throws behind you, he’s got something in mind.”