Frontier League The
Milwaukee Brewers selected Anderson in the 32nd round of the
2012 MLB draft. He did not sign with the Brewers and played in the
independent baseball Frontier League for three seasons. He played for the
Rockford RiverHawks/Aviators in 2012 and 2013, and for the
Frontier Greys in 2015. He played in nine games for the Single-A
Cedar Rapids Kernels in 2015, recording a 0.75 ERA with 12 strikeouts and four
saves over 12 innings. Anderson split the 2016 season between Cedar Rapids and the High-A
Fort Myers Miracle, accumulating a 4–3 record with a 2.65 ERA, 75 strikeouts, and 13 saves across innings pitched. In 2017, he played for Fort Myers and the Double-A
Chattanooga Lookouts, registering a combined a 4–1 record with a 1.00 ERA, 57 strikeouts, and 11 saves over innings pitched. Anderson spent the 2018 season with the Triple-A
Rochester Red Wings, going 8–2 with a 3.30 ERA, 88 strikeouts, and four saves over 60 innings of work. the Marlins subsequently added him to their
40-man roster. Anderson made the Marlins' 2019
Opening Day roster. On March 28, 2019, he made his major league debut against the
Colorado Rockies. Anderson retired
Ryan McMahon, the only batter he faced. Anderson collected his first major league win on May 21 in a 5–4 11-inning game against the
Detroit Tigers. He pitched the final two innings, allowing no runs while striking out a career-high five batters. By the end of July, Anderson had appeared in 45 games with 69 strikeouts in innings for the Marlins.
Tampa Bay Rays On July 31, 2019, Anderson was traded to the
Tampa Bay Rays (along with
Trevor Richards) in exchange for
Jesús Sánchez and
Ryne Stanek. After the trade, he had an ERA of 2.11 in innings with 41 strikeouts. He was named to the
Baseball America All-Rookie team and won the
Dick Siebert Award, given by Minnesota
baseball writers to the best player from the Upper Midwest, in 2019. In 2020, Anderson went 2–1 with six saves and an 0.55 ERA in innings over 19 games. After the season, he was named to the
All-MLB Team. On March 25, 2021, it was announced that Anderson had suffered a partial tear of his elbow ligament and would miss time until at least the All-Star break. On March 26, Anderson was placed on the 60-day
injured list (IL). Anderson was activated from the IL on September 12 to make his season debut. Anderson was able to work to a 4.50 ERA in 6 appearances for the Rays in 2021. On October 27, Anderson underwent right elbow surgery to repair his ulnar collateral ligament with an internal brace procedure. The surgery was an alternative to
Tommy John surgery, but Anderson was projected to remain out through the 2022 All-Star break. On March 22, 2022, Anderson signed a $845,000 contract with the Rays, avoiding salary arbitration. On August 22, Anderson was activated from the IL and optioned to Triple-A
Durham Bulls. On November 9, Anderson was placed on outright waivers. After clearing waivers, Anderson became a free agent the next day.
Atlanta Braves On November 11, 2022, Anderson signed a one-year, non-guaranteed split contract with the
Atlanta Braves. Anderson was optioned to the Triple-A
Gwinnett Stripers to begin the 2023 season. However, after it was revealed that
Raisel Iglesias would begin the year on the IL, the Braves announced that Anderson had made the
Opening Day roster as part of the bullpen. After posting a 3.06 ERA with 36 strikeouts through 35 games, Anderson was placed on the 60-day IL with a right shoulder strain on July 13, 2023.
Kansas City Royals On November 17, 2023, the Braves traded Anderson to the
Kansas City Royals in exchange for cash considerations. In 37 relief outings for the Royals, he compiled a 3–1 record with 1 save, and a 4.04 ERA with 29 strikeouts and 15
walks across innings pitched. Anderson was
designated for assignment by the Royals on July 13, 2024, after the team acquired
reliever Hunter Harvey in a
trade with the
Washington Nationals. The Royals released Anderson on July 18.
Los Angeles Dodgers On July 21, 2024, Anderson signed a minor league contract with the
Los Angeles Dodgers. He pitched innings over three games, and allowed three runs on three hits and three walks for the Triple-A
Oklahoma City Baseball Club. He made 2 scoreless appearances for the Triple-A
Norfolk Tides, striking out 2 batters over 2 innings of work. He elected free agency following the season on November 4.
St. Louis Cardinals On February 7, 2025, Anderson signed a minor league contract with the
St. Louis Cardinals. In 17 appearances for the Triple-A
Memphis Redbirds, he posted an 0–1 record and 6.20 ERA with 20 strikeouts across innings pitched. The Cardinals released Anderson on May 30.
Colorado Rockies On May 30, 2025, Anderson signed a minor league contract with the
Colorado Rockies. In 14 outings for the Triple-A
Albuquerque Isotopes, he logged a 1-1 record and 5.11 ERA with 15 strikeouts and four saves across innings pitched. On July 25, the Rockies selected Anderson's contract, adding him to their active roster. In 12 appearances for Colorado, he struggled to a 6.14 ERA with 10 strikeouts across innings pitched. On August 29, Anderson elected free agency rather than accept an outright assignment to Triple-A Albuquerque.
Seattle Mariners On August 31, 2025, Anderson signed a minor league contract with the
Seattle Mariners. He pitched in six games for the Triple-A
Tacoma Rainiers, logging a 1-0 record and 3.18 ERA with 10 strikeouts across innings pitched. Anderson elected free agency following the season on November 6.
Athletics On November 12, 2025, Anderson signed a minor league contract with the
Athletics. ==Personal life==