John Richard Gelnar (born June 25, 1943) is an American former Major League Baseball pitcher.

He signed with the Pittsburgh Pirates as an amateur free agent in 1963, after his freshman year at Oklahoma.

[2] He was traded by the Brewers with José Herrera to the Detroit Tigers for Jim Hannan on May 11, 1971.

[3] After his baseball career ended, Gelnar worked in the oil industry before becoming a farmer and rancher in Hobart in his native Oklahoma.

[5] This biographical article relating to an American baseball pitcher born in the 1940s is a stub.