The Sabres selected Samuelsson, 20, in the second round of the 2018 NHL Draft (32nd overall). He recently completed his sophomore season at Western Michigan, where he tallied 14 points (2+12) in 30 games and served as an alternate captain.

"We are very pleased with Mattias' growth both at Western Michigan and on the international stage," Sabres general manager Jason Botterill said. "He possesses a unique combination of size, speed and skill, and we look forward to working with him on his next steps as a pro."

Video: Behind the scenes with Mattias Samuelsson

Samuelsson has twice represented the United States at the IIHF World Junior Championship, earning a silver medal in 2019 and serving as captain of Team USA in 2020.

The 6-foot-4 defenseman concluded his college career with 26 points (7+19) in 65 games. He was an All-NCHC honorable mention this season and was a finalist for the conference's Defensive Defenseman of the Year Award.

Samuelsson is the second Western Michigan player to sign with the Sabres this week, joining forward Dawson DiPietro.

"I think he's just a presence out there," DiPietro said of Samuelsson during development camp last summer. "He's big guy. He's a big body out there. He gets it done every time he's on the ice. He doesn't really have to say much, but he gets the job done. He's a physical guy. He's a guy people look up to."