Mittelstadt was a restricted free agent entering his fourth NHL season after being selected with the eighth pick in the 2017 draft. The 22-year-old from Minnesota has struggled with inconsistency after being pegged as a potential top-two-line center.
Mittelstadt managed 12 goals and 25 points in 77 games with the Sabres during his rookie season in 2018-19. He split last between Buffalo, where he had four goals and nine points in 31 games, and the minors to develop his game. He finished with nine goals and 25 points in 36 games with Rochester of the American Hockey League.
The Sabres open training camp on Dec. 31, when Mittelstadt will have to compete to earn a regular role on a revamped team that incudes the offseason additions of Taylor Hall and Eric Staal, who is projected to fill the second-line center spot.
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