OAKLAND — The ritual occurs after every victory at Oakland Coliseum. The members of the Athletics — the perpetually underfunded, unimpeachably hip, ceaselessly evolving playoff contenders from the East Bay — gather as a group on the splotchy green carpet of their clubhouse. All eyes turn toward a miniature basketball hoop affixed above a locker. The star of the night gets a foul shot. A swarm of insults awaits an errant shooter.



“Everyone is pretty bad,” outfielder Mark Canha said. “It’s usually a miss. And then we all boo him and humiliate him in front of everyone.”



Inside the hothouse of the big leagues, amid the marathon of the 162-game slog, the taunts bind the players. Several A’s have been teammates for years. Others have been together for months. Some have only been part of the group for days. All are welcome. Cohesion is crucial as Oakland mounts another unlikely bid for the postseason.



The...