The rookie first-round draft pick was sent down to AHL Rochester on Saturday, before Buffalo's 4-2 loss to Colorado. The Sabres made the move to free up a roster spot to activate fellow rookie defenceman Nikita Zadorov off injured reserve.
Ristolainen, drafted eighth overall in June, has no points in eight games this season.
At 1-8-1, the Sabres are off to their worst start in team history. They close out a three-game homestand against Boston on Wednesday.
Rookie forward Corey Tropp practiced for the first time Monday since breaking his jaw in a fight during a preseason game against Toronto on Sept. 22.
Life's about opportunity and how you respond to that opportunity, and obviously he must have some swagger about him, some confidence about him, because he was solid. He made some good saves. He was 6-foot-3 on every shot, which is a good thing for a goalie. He played well. We got a win.
— Maple Leafs coach Mike Babcock on rookie goaltender Garret Sparks, who made 24 saves in his first NHL start, a 3-0 win vs. Oilers
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