Jamie Benn, Ryan Garbutt and Valeri Nichushkin all scored for the Stars, who dropped the first two games of the best-of-seven series in Anaheim.
Frederik Andersen made 19 stops in the loss for the Ducks, who lost defenseman Stephan Robidas to a fractured right leg in the game.
Robidas was injured early in the second period during a collision with Garbutt, and was taken to a local hospital. The team later said that he suffered a fractured leg and will likely miss the rest of the playoffs.
He was making his return to Dallas, which traded him to Anaheim in March. At the time of the trade, he was recovering from a fracture in the same leg -- a bit lower than this one -- that kept him off the ice for close to four months.
Game 4 is Wednesday in Dallas.