Right-winger Rickard Rakell scored on a deflection at 5:12 of overtime to lift Anaheim 5-4-over Winnipeg and gain a strangle-hold of their Western Conference first-round playoff series - a 3-0 lead in a best-of-seven.
Rakell redirected blueliner Francois Beauchemin's point blast for his first goal of the series, giving the Ducks the commanding lead in the series.
Elsewhere, the New York Rangers built a two-goal lead before holding on for a narrow victory over the Pittsburgh Penguins to take a 2-1 lead in their Eastern Conference first-round playoff series.
Left-winger Carl Hagelin scored on a breakaway in the first period and centre Chris Kreider netted in the second for a 2-0 New York lead.
Right winger Patric Hornqvist broke up a potential shutout for Rangers goaltender Henrik Lundqvist with a third-period goal as the Penguins out-shot the visitors 13-7 in the final frame but were unable to find an equaliser.
Minnesota's top line of Zach Parise, Mikael Granlund and Jason Pominville combined to score two goals late in the second period as the Wild blanked St Louis 3-0 to grab a 2-1 lead in their Western Conference first-round playoff series.