The New York Islanders, looking for some more firepower, traded defenseman Jean Potvin and wing J. P. Parise to the Cleveland Barons Tuesday for center Wayne Merrick and future considerations, and then went out and knocked off the Colorado Rockies, 7-4.

"In analyzing our positions, we found ourselves in second place," said Islander general manager Bill Torrey, whose team trails Philadelphia by two points in the Patrick Division. "In some areas, we were making progress; in others we weren't. We felt we still couldn't match Montreal and Philadelphia in speed, offense and playmaking.

Potvin scored a goal late in the second period to ice the game for New York as Bob Bourne and Clark Gillies each scored twice, with Gillies adding an assist.

After John Van Boxmeer converted a power-play opportunity in the first period to open the scoring, Gillies, playing as substitute left wing on the fourth line, put the Islanders ahead with consecutive scores at 10:53 and 14:49 of the first.

The Rockies drew close again in the second when rookie Joe Contini beat Islander goalie Billy Smith and went ahead when newly acquired Bob Necly scored unassisted on a 35-footer.

Rangers 3, Bruins 2

Pat Hickey scored two goals, including the game-winner, to trigger the Ranger victory, snapping Boston's 15-game unbeaten streak at Boston Garden. Hickey, whose first goal cut Boston's 2-0 lead in half, netted the winner when he took a loose puck from outside his crease and skated through the Bruins. Hickey crashed into Boston goalie Gilles Gilbert and the puck bounced over Gilbert into the net at 11:23 of the final period.