A pitch in baseball that, while never prevalent in its history, has existed at least as far back as the early 20th century. Despite its name, the ball is gripped with the fingertips (and some pitchers are fussy about manicures) and thrown so, ideally, it doesn't rotate, as all other pitches do. Thrown properly, the ball should "knuckle" - behave unpredictably. It can give a catcher fits. Thrown by Hoyt Wilhelm, Phil Niekro, Jim Bouton, et al; current knuckleballers include Tim Wakefield.