Andrew Robert Knizner (/ˈkɪznər/ KIZ-nər;[1] born February 3, 1995) is an American professional baseball catcher in the Washington Nationals organization.

[2] During his senior year, he was captain of the school's baseball team while batting .453 with five home runs, leading Hanover to a Virginia Class AAA state championship.

[8][9] As a junior, he batted .292 with six home runs and 30 RBIs, along with compiling a .991 fielding percentage and throwing out 16 of 37 base runners attempting to steal.

[19] Knizner began 2018 with Springfield and after batting .333/.412/.467 with two home runs and 18 RBIs in 27 games, he was promoted to the Memphis Redbirds.

On July 24, he hit his first major league home run, also against the Pittsburgh Pirates, leading St. Louis to a 14–8 win.

[29] Knizner finished his 2019 rookie regular season in St. Louis batting .226 with two home runs and seven RBIs over 53 at-bats.

[30] For the 2021 season, Knizner returned as Yadier Molina's backup, taking 161 at-bats over 63 games, slashing .174/.281/.236 with one home run, nine RBIs, and seven doubles.

[31] Knizner saw more playing time in 2022—260 at-bats in 96 games—as Molina dealt with injuries for much of the season, and slashed .215/.301/.300 with four home runs and 25 RBIs.

[32] On May 6, it was announced that Knizner would take over as the primary catcher as the Cardinals began to shift Willson Contreras to designated hitter.