Christensen fired a wrist shot that went off the left post, and then off the back of goaltender Niklas Backstrom and into the net.
The contest ended regulation in a 2-2 tie after Atlanta right wing Colby Armstrong scored his 10th goals this season on the power play in the third period.
Minnesota got Brian Rolston's 25th goal (power play in the first) and Brett Burns' 12th (power play in the third). Both players had one assist and Backstrom stopped 24 of 26 shots in regulation for the Wild, who lost their third straight game.
Before the loss, Minnesota was 5
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