It was a 2-2 game heading into the third, but Smith put the Senators in front for good by scoring on a slap shot 6:42 into the period. MacArthur produced what turned out to be the winning goal less than five minutes later.
Winnipeg had a three-game winning streak halted. Al Montoya gave up the four goals on 29 shots.
Ottawa defeated Winnipeg for the sixth time in eight meetings.
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