Donald Marek Snelten (born May 29, 1992) is an American professional baseball pitcher in the Chicago White Sox organization.

He spent 2014 with the Salem-Keizer Volcanoes and Augusta Greenjackets, posting a combined 4–1 record and 2.56 ERA in 29 relief appearances, and 2015 with the San Jose Giants and Augusta, pitching to a combined 5–11 record and 3.44 ERA in 23 total starts between the two teams.

On April 28, 2018, the Giants called up Snelten ahead of a double-header and he made his major league debut in the second game.

On December 29, 2019, Snelten signed with the Tampa Bay Rays, getting exposure after throwing 99 mph in viral videos seen on Rob Friedman's FlatGround Twitter account.

[14][15] Snelten did not play in a game in 2020 due to the cancellation of the minor league season because of the COVID-19 pandemic.

In 2023, Snelten played in 30 games for the Triple–A Scranton/Wilkes-Barre RailRiders, struggling to a 7.50 ERA with 48 strikeouts and 2 saves in 36.0 innings of work.

[19] On July 31, 2023, Snelten signed with the Chicago Dogs of the American Association of Professional Baseball.

[25] On January 16, 2025, Snelten signed a minor league contract with the Chicago White Sox.