The former Atlanta Thrashers had gone 0-3-0 since moving to Winnipeg before the start of the season. They logged their initial victory of the year and first in their new home thanks to a pair of first-period goals.
Wellwood received a pass from Alex Burmistrov on a break off the opening face-off, created when a Pittsburgh defenseman fell and the Jets center buried the puck in the net for the fourth-quickest goal in franchise history.
Tanner Glass added a marker with 1:23 left in the period for Winnipeg.
Ondrej Pavelec turned aside 28-of-29 shots as the Jets improved to 1-1 at home.
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