The Utah Mammoth are set to add another young forward to their group as their rebuild continues.
Peterka was slated to become a restricted free agent on July 1.
Peterka posted a career-high 68 points (27 goals and 41 assists) in 77 games with the Sabres this past season.
The 23-year-old from Munich was drafted in the second round, 34th overall, by the Sabres in 2020.
He has 150 career points (67 goals and 41 assists) in 238 games over parts of four seasons with Buffalo.
He’ll now join a young core with forwards Logan Cooley, Dylan Guenther and Daniil But, who signed a three-year, entry-level contract with the Mammoth in May.
Meanwhile, the Sabres acquire the 23-year-old Doan, who had seven goals and 12 assists in 51 games for Utah last season, and the 25-year-old Kesselring, who finished with a career-high seven goals and 22 assists in 82 games.
The Sabres have missed the playoffs the past 14 years.
