John Picus Quinn (born Joannes "Jan" Pajkos, July 1, 1883 – April 17, 1946) was a Slovak-American professional baseball player.

[2] Born in Stefuró, Hungary (modern-day Štefurov, Slovakia), Quinn emigrated to America as an infant with his parents Michael Pajkos and Maria Dzjiacsko, arriving in New York on June 18, 1884.

Quinn spent his early years working as a swimmer and blacksmith, while playing recreational ball for mining teams.

While watching a semi-pro game in Connellsville, the 14-year-old Quinn threw a foul ball back from the stands to the catcher, hitting his mitt right in the middle.

He is furthermore the oldest pitcher to start games in the World Series (with the Philadelphia Athletics, in 1929) and on Opening Day (with the Brooklyn Dodgers, in 1931).

During his career, Quinn played alongside 31 different members of the Baseball Hall of Fame and collected two World Series rings in three tries.