A week after writing this entry, I found this book in a used bookstore
An informal term meaning a sudden unexplained loss of skill in sports, especially sub-skills requiring precision and accuracy.
In baseball, this might be a prolonged “slump.” In golf, a sudden inability to putt well. In basketball, an unexplained reduction in the ability to shoot free throws.
The term was invented by Tommy Armour, a golfer in the 1920s, to describe problems with his game.
Why I Looked It Up
On an episode of Happy Endings, Dave suddenly lost the ability to kick in kickball. Max and Brad kept telling him he had “the yips.”
I found this article: How Tyler Matzek Conquered the Yips to Become a World Series Champion
[…] a few days later, in a game of catch, when Tyler Matzek, major league pitcher, found that all of a sudden he could not throw a baseball on target at all.
According to [sports psychologist] Cohn, sometimes they develop in the wake of trauma, whether personal or professional, and often emerge during times of incredible stress in an athlete’s life. Every couple of years, Atlanta pitcher Luke Jackson says, someone will show up to spring training with a full-blown case. “You see them struggling,” Jackson says. “You know that guy is doing everything in his power to throw a baseball over the plate. He just can’t.”
The article is the story of Matzek specifically, but also an investigation of the yips as a phenomenon.