On the play, Roussel skated in on net, switched to his backhand and sent a shot past Crawford high into the net, breaking a 3-3 tie.
Erik Cole, Alex Chiasson and Valeri Nichushkin also scored as Dallas won for the first time in seven meetings against the Blackhawks and broke a two-game overall losing streak.
Dallas goalie Kari Lehtonen turned in an outstanding effort, stopping 47 of a career-high 50 shots.
Crawford made just 14 saves for Central Division-leading Chicago, which had its six-game winning streak snapped.
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