John David Gaub (born April 28, 1985) is a former Major League Baseball pitcher.

Prior to playing professional baseball, Gaub attended South St. Paul High School and then the University of Minnesota.

He pitched for the Lake County Captains in 2008, making 34 relief appearances and going 1-1 with a 3.38 ERA.

On December 31, 2008, he was traded with minor leaguer Christopher Archer and Jeff Stevens to the Cubs for Mark DeRosa.

[citation needed] On May 21, 2012, Gaub was designated for assignment by the Rays and was claimed by the Texas Rangers a few days later.