Joseph Daryl Wiemer (/ˈwiːmər/ WEE-mer;^[1] born February 11, 1999) is an American professional baseball outfielder for the Milwaukee Brewers of Major League Baseball (MLB). He was drafted by the Brewers in the fourth round of the 2020 Major League Baseball draft. He made his MLB debut in 2023.

Wiemer attended Bedford Senior High School in Temperance, Michigan. He enrolled at the University of Cincinnati and played college baseball for the Cincinnati Bearcats.^[2] In 2019, he played collegiate summer baseball with the Harwich Mariners of the Cape Cod Baseball League and was named a league all-star.^[3] He was drafted by the Milwaukee Brewers in the fourth round of the 2020 Major League Baseball draft.^[4][5]

Wiemer made his professional debut in 2021 with the Carolina Mudcats before being promoted to the Wisconsin Timber Rattlers.^[6][7] Over 109 games between the two teams, he slashed .295/.403/.556 with 27 home runs, 77 runs batted in, and 30 stolen bases.^[8] In 2022, Wiemer played in 127 games split between the Double-A Biloxi Shuckers and Triple-A Nashville Sounds. In 484 at-bats, he hit .256/.336/.465 with 21 home runs, 77 runs batted in, and 31 stolen bases.

After initially missing out on the Opening Day roster, on March 30, 2023, the Brewers announced that Wiemer was promoted to the major leagues. On April 1, Wiemer hit a double in his major league debut against the Chicago Cubs at Wrigley Field on the first pitch he saw.^[9] On April 5, Wiemer hit his first major league home run in a win over the New York Mets at American Family Field.^[10] On May 13, Wiemer delivered a walk-off sacrifice fly in a win over the Kansas City Royals.^[11] On June 6, he recorded his first career walkoff hit, a single against the Baltimore Orioles.^[12] In 132 games during his rookie campaign, Wiemer batted .204/.283/.362 with 13 home runs, 42 RBI, and 11 stolen bases.

Wiemer was optioned to Triple–A Nashville to begin the 2024 season.^[13]