James Jason Mecir (born May 16, 1970) is an American former Major League Baseball pitcher who played for five teams over an 11-year career between 1995 and 2005.

Mecir is notable for having overcome a club foot to become an effective Major League pitcher, as well as for regularly throwing a screwball.

He spent 4+1⁄2 years as a member of the Oakland Athletics and is prominently mentioned in Michael Lewis's bestselling book Moneyball: The Art of Winning an Unfair Game.

He played for Seattle in 1995, the New York Yankees in 1996[2] and 1997, the Tampa Bay Devil Rays from 1998 to 2000, the Oakland Athletics from 2001 to 2004, before spending the last year of his career with the Marlins.

In 2003, Mecir received the Tony Conigliaro Award, given annually to the player who most effectively overcomes adversity to succeed in baseball.