曲球

曲球（Curveball）棒球中的一種球路. 握球時食指與中指握在球的外側縫線處，出手時藉著手腕的順時針方向旋轉與手指的向下施力，使球造成旋轉，進而產生垂直向分力，加上重力的作用，會使球在進入本壘板前的垂直掉落幅度遠大於快速球. 曲球於1870年代首次出現，是相當古老的一種變化球. * Version 1: Candy Cummings was the inventor of the curveball * Version 2: Fred Goldsmith: co-inventor of the curveball or pitcher who gave first recorded demonstration of the curveball? * Aerodynamics of a Curveball in Navier-Stokes Flow * How to Throw a Curveball – wikiHow page outlining technique