Johns Joseph Hamilton (born September 9, 1970) is an American former Major League Baseball pitcher who played professionally for nine seasons, recording a 74–73 win–loss record, a 4.44 earned run average (ERA) and 894 strikeouts.

Hamilton had stints in training camps and the minor leagues with some of the Padres and Reds affiliates.

Hamilton decided against signing with the Orioles,[2] opting instead to play college baseball for Georgia Southern University.

[4] He was one of nine finalists for the Golden Spikes Award, and he earned Second Team All-American honors from The Sporting News and Baseball America.

[4] Hamilton held the Georgia Southern baseball record for appearances, starts, complete games, innings pitched and strikeouts until 1995.

[10] Following the draft, Hamilton joined Team USA in Canada in preparation for the Olympics.

With the Wichita Wranglers he went 3–0 with a 2.86 ERA in six starts and pitched 342⁄3 innings during his time with the team.

[2] In his fourth year with San Diego in 1997, Hamilton started on Opening Day for the Padres.

[2] Hamilton suffered a shoulder injury that was described as an inflammation of the rotator cuff and bursa sac.

[18] Hamilton called the injury "real scary", saying that he feared he may lose the ability to throw 100 miles per hour (160 km/h).

[19] With the Padres in 1998, Hamilton's last season in San Diego, he had a 13–13 record, 4.27 ERA in 34 starts and 2171⁄3 innings pitched.

[2] After five years with San Diego, Hamilton was traded to the Toronto Blue Jays on December 12, 1998, for Peter Tucci, Carlos Almanzar, and Woody Williams.

[2][24] Analysts believe that Toronto acquired Hamilton if Roger Clemens's trade request was successful.

[25] Hamilton began the 1999 season with the Syracuse SkyChiefs, the Triple-A affiliate of the Blue Jays.

[26] For the second time in his career, Hamilton began the season in Syracuse and went 3–2 with a 3.66 ERA in six games and 391⁄3 innings pitched.

[28] Hamilton signed with the Cincinnati Reds on August 17, 2001,[2][29] and was optioned to their Triple-A team, the Louisville Bats.

[1] Despite only recording one win for the team the year before, Hamilton was named the Reds' 2002 Opening Day starter.

[34] Hamilton was signed by the St. Louis Cardinals on January 6, 2003,[35] but was released on March 26, 2003, after struggling in spring training.

[2] The Padres re-signed Hamilton on December 10, 2003,[2] and optioned him to their Triple-A affiliate, the Portland Beavers.