The 19-year-old Grigorenko began the season in the NHL, but struggled. He scored two goals in 18 games before being demoted to the Quebec Remparts of the Quebec Major Junior Hockey League on Jan. 11.
Grigorenko initially refused to report to Quebec, preferring to develop in the AHL. An agreement between the NHL and the Canadian Hockey League does not allow teenagers to play in the AHL.
The Sabres tried to send Grigorenko to Rochester on a conditioning assignment in November, but the NHL denied the request. With the QMJHL season over, Grigorenko is allowed to play in the AHL.