The fosh, fosh ball, or fosh change is a seldom used pitch in Major League Baseball described as "a cross between a split-fingered pitch and a straight change-up".^[1] It is designed to fool a batter expecting a fastball to have to contend with a slower pitch. The pitch has a grip like a fastball, but the index and middle fingers are spread slightly across the baseball, and the ring and little finger wrap around the side of the ball.^[2] If thrown properly, it has characteristics like a breaking change-up or an off-speed split-finger fastball.

The origin of the fosh is unknown. Mike Boddicker was the first pitcher known to throw it, having tried it in the 1980s.^[3] As pitching coach for the Boston Red Sox, Al Nipper taught the pitch to Jeff Suppan in 1995,^[3] and Tom Gordon and Roger Clemens in 1996.^[4] Other pitchers who have used it in a game are Jason Frasor,^[2] Trevor Hoffman,^[2] Johan Santana,^[2] Jason Bere, Carl Pavano,^[5] and Carlos Rosa.^[6]

There are various etymologies for the term "fosh". According to The Neyer/James Guide to Pitchers: An Historical Compendium of Pitching, Pitchers, and Pitches, three derivations are known. One is that Earl Weaver described it as "a cross between a fastball and a dead fish".^[3] Another is a description by David Nied, who said the term sounds "like the perfect word for the movement of the pitch".^[3] A third derivation, from Al Nipper, is that fosh is an acronym for "full of ...".^[7]