Mathieu Cadieux made 34 saves for No. 7 Plattsburgh, which scored twice in the first period and handed No. 1 Oswego its first loss of the season, 2-1 on Saturday.
Paul Puglisi scored a four-on-four goal and Alex Brenton added a short-handed score for the Cardinals (7-2-1, 6-1-1 SUNYAC).
Chris Muise brought the Lakers (8-1, 7-1) within one with a power-play goal in the third period.
Andrew Hare made 24 saves for Oswego.