With two points on the night, McTavish moved into a tie for second place among NHL rookies in points and assists. The 19-year-old leads Anaheim in power-play points (10) and co-leads in power-play goals (four).
McTavish's goal was his ninth of his 48-game NHL career, fourth-most in Ducks history by a teenager.
Skating in his 850th NHL game, Fowler grabbed an assist on the goal to move within one of becoming the fifth player to record 300 assists as a Duck.
Zegras also collected an assist on the power-play goal. He now has four in his last four games and a team-leading 19 on the season.
That two-goal cushion would be more than enough help for Gibson, who was spectacular all night long and helped out by Anaheim's stingy defensive effort. The Ducks excelled, especially late in the game, at keeping Dallas to the perimeter and out of the slot, a strategy head coach Dallas Eakins would be crucial to success at his pregame press conference.
The Ducks would be tested one last time on a late third period penalty kill after Terry was whistled for tripping Dallas captain Jamie Benn, but the Ducks shorthanded unit once again came up big to lock down a 2-0 victory.
After struggling heavily early in the season the penalty kill, the Ducks have now eliminated 16 of their opponents' last 17 power plays.
The Ducks continue their 10-game homestand Friday night against San Jose.