Sabres Reassign D Radim Mrtka to Rochester Amerks from WHL

The Buffalo Sabres returned Radim Mrtka to the Rochester Americans on Tuesday, pulling their most prized defensive prospect out of Seattle's WHL playoff picture and dropping him into one of their own. The timing is deliberate: Rochester is pushing for postseason position, and the 18-year-old Czech blueliner arrives with more seasoning than he had at any previous point in his professional trajectory.

Mrtka is not a typical AHL assignment. Buffalo selected him 9th overall in the 2025 NHL Draft, making him the franchise's first first-round defensive pick since Owen Power went first overall in 2021. NHL Central Scouting Services ranked him the fifth-best North American skater in that entire draft class. At 6-foot-6 and 218 pounds, he is the kind of right-shot defenseman that scouts call a generational body type — the kind you can build a blue line around for a decade.

His 2025-26 campaign has been defined by steady upward movement. After a brief initial AHL assignment in October 2025, when Buffalo chose to send him to Rochester rather than return him to junior alongside center Noah Ostlund and defensemen Vsevolod Komarov and Zachary Metsa, Mrtka went back to the Seattle Thunderbirds for the WHL season. He put up 34 points in 43 regular-season games, nearly matching the 35 he posted across 43 games in 2024-25 when he earned top draft consideration with a plus-10 rating. Then came the World Juniors.

Representing Czechia in January, Mrtka was part of a team that eliminated Canada for the third consecutive year in the semifinals before falling to Sweden 4-2 in the gold medal game. The silver medal added an international credential to a resume that is filling up fast for someone born on June 9, 2007.

The earlier Rochester stint, brief as it was, left an impression. Amerks head coach Mike Leone singled out how well Mrtka "scans the ice," a trait that separates defensemen who survive the pro game from those who thrive in it. Mrtka logged big minutes from the start, often playing alongside veteran defenseman Jack Rathbone, and recorded his first professional point in the season-opening victory. In Seattle, Thunderbirds captain Braeden Cootes, himself a Vancouver Canucks prospect, described Mrtka simply as "so competitive and hardworking."

What makes this second reassignment significant is the context around it. A loan back to junior is a developmental placeholder. A second professional assignment during a playoff race is a statement. Rochester's blue line gets a 6-foot-6 two-way presence who can move the puck from the right side, and Mrtka gets the high-stakes minutes that could make the case for a full-time jump to Buffalo as soon as next fall. The Sabres signed him to a three-year entry-level contract on July 15, 2025. The clock on that deal is ticking, and so is his development window. This AHL playoff run may be the last audition before the real thing.