Halonen began his collegiate career for Michigan Tech during the 2018–19 season, where he recorded 12 goals and nine assists in 35 games. He led the Huskies and all Western Collegiate Hockey Association (WCHA) rookies with 12 goals. Following the season he was named to the All-WCHA Rookie Team and awarded the Norbert Matovich Memorial Outstanding Freshman Award.[1] During the 2019–20 season in his sophomore year, he recorded 12 goals and 10 assists in 39 games, and ranked fourth on the team with 22 points. During the 2020–21 season in his junior year, he recorded eight goals and 10 assists in 28 games, and ranked third on the team with 18 points. He ranked sixth in the nation with four game-winning goals.[2]
During the 2021–22 season in his senior year, he recorded 21 goals and 23 assists in 37 games. He led the Central Collegiate Hockey Association (CCHA) in points (36) and goals (16), and ranked fifth in the CCHA in assists (20) during conference games. He recorded six goals and eight assists with 45 shots on goal during the month of February. On February 11, 2022, he became the 68th player in program history to reach 100 points in a career.[3] He was subsequently named the CCHA Forward of the Month.[4]
On March 28, 2022, Halonen signed a two-year, entry-level contract with the New Jersey Devils beginning with the 2022–23 season. He was assigned to the Utica Comets, the American Hockey League (AHL) affiliate of New Jersey, on an amateur tryout contract for the remainder of the 2021–22 season.[9] On April 2, he recorded his first professional goal in his second career game.[10]
Halonen started the 2023–24 season on injured reserve.[11] On December 30, 2023, he was activated from injured reserve and assigned to Utica.[12] The Devils recalled Halonen on February 23, 2024, after Nathan Bastian was placed on injured reserve,[13] and he made his NHL debut two days later, in a 4–1 loss to the Tampa Bay Lightning.[14] He finished the AHL season with 20 goals and 29 points in 35 games, leading the Comets with nine power play goals.[15]
On May 16, 2024, the Devils re-signed Halonen to a two-year, two-way contract with a $775,000 cap hit.[15]
Personal life
Halonen has 10 siblings, an older sister and older brother, three younger sisters, and five younger brothers.[2] He is the cousin of professional ice hockey player Blake Pietila.[16]