Inside Major League clubhouses, it a taboo subject, confined to the office of a team psychologist or to the walls encompassing a player's brain.
Experts take extra precaution with how they define it, fearful of classifying a player as having some deficiency or being a liability.
To those observing, it seems like a predicament with a simple solution. To those enduring, there are no answers, only a proliferating number of questions.
Much has been written about "the Yips," but much about the condition remains clouded.
"We really don't talk about it as baseball players," said 19-year veteran Jason Giambi. "It's just this unwritten rule. You feel terrible for [those experiencing it]."
The Yips is no mythological plague. For reasons unknown, players can encounter a mental hurdle that flat-out won't permit them to complete one of the game's mundane on-field tasks. Infielders suddenly can't find the first baseman's glove on routine throws. Catchers can't execute the simple task of returning the ball to the pitcher.
"It's the real deal," said Jason Tyner, who played in the big leagues from 2000-08. "These guys are throwing the ball 50 feet off their mark. Or they spike one halfway. I don't even know how to describe it."
Dr. Charlie Maher, Indians sports psychologist, avoids using the term "yips," and instead refers to the circumstance as "misplaced focus." That removes the notion that the player is suffering from some sort of daunting ailment.
"If their focus really is misplaced, it's on results," Maher said. "It's on what people are thinking. It gets them away from the fluidity of the process of the game. As a result, it snowballs. They start to judge themselves. They start to tense themselves up. The end result is that the ball is not going where it's supposed to go."
From 1968-72, Steve Blass compiled 78 wins, a 3.05 ERA, an All-Star Game nod and a second-place finish in National League Cy Young Award balloting. Over that stretch, he averaged three walks per nine innings. He unraveled in 1973, when he walked 84 batters in 88 2/3 innings, posted a 3-9 mark and a 9.85 ERA. He last pitched in a Major League game in 1974, one day before his 32nd birthday. He officially retired in the spring of 1975, and the phrase "Steve Blass disease" was coined to identify a player who suddenly loses the ability to accurately throw a ball.
The syndrome has notably afflicted such players as Steve Sax, Mackey Sasser and Chuck Knoblauch. After he proved incapable of throwing the ball to first base, Knoblauch relocated to left field from his original position of second base.
Nationals third baseman Ryan Zimmerman, a Gold Glove Award recipient in 2009, made four throwing errors in a five-game span in April. His manager, Davey Johnson, attempted to pin the problem on Zimmerman's surgically repaired shoulder. Zimmerman, however, deflected that excuse and hinted that the issue was a mental one.
"People make errors. It's going to happen again before the year is over," Zimmerman said. "Everyone is going to make errors. It's part of the game. Nobody wants it to happen. Of course, you feel bad. You play baseball long enough, that kind of stuff happens. It's part of the game. If you let it consume you, that's what gets you."
Tyner witnessed pitcher Matt Garza, then his teammate in Tampa Bay, struggle to complete ordinary throws to first base.
"If you bunted on him, he's throwing it down the right-field line," Tyner said. "It wasn't even close. You'd see him over on a back field working on it and it'd look like a 6-year-old trying to throw to first base. He could throw 95 mph wherever he wants to the batter, but he could not throw the ball to first base."
Indians closer Chris Perez has seen infielders and pitchers alike demonstrate symptoms of the Yips, with their minds only getting in their way.
"They're telling themselves before it's hit, 'Don't throw it in the dirt,'" Perez said. "And of course, they throw it right in the dirt."
Maher offers players three recommendations for when they are dealing with a mental hurdle: don't let your mind float, relax and accept what's at hand, and deal with the play as it happens. Maher advises players to take baby steps to gradually prove to themselves that they can return to form. He'll have them make plays on a back field with no onlookers or participate in a simulated game.
"It's very difficult to deal with in the Major League environment because of all of the factors and all of the people who are around with all of the things going on," Maher said. "You have to put them in a situation where they can work on something without feeling like they're being judged."
Dr. Richard Crowley, who penned a book on overcoming the Yips, said it's not worth anyone's time to determine the cause of the malady.
"Even if you knew exactly what caused your yips, what the heck do you do with it? It's just information," Crowley said. "It doesn't change it."
Crowley takes players through a set of mental exercises until their anxiety and concerns dissipate. He cautions, however, that there is no strict set of instructions to follow to conquer the condition.
"There's no explanation on the planet to get over this," Crowley said. "When you're Superman and you get near kryptonite, you're beside yourself. You can't muster up all that stuff. All the information in the world cannot change a ballplayer who has this particular struggle."