Jackson Houck had a goal and an assist for Vancouver (22-29-3), while Jakob Stukel, Jesse Roach and Zane Jones also scored. Cody Porter made 26 saves for the win.
Lane Pederson opened the scoring for Seattle (27-20-6). Jerret Smith and Cory Millette both had power-play goals for the Thunderbirds, while Ryan Gropp tied it 4-4 at the 11:33 mark of the third period. Logan Flodell stopped 29 shots for Seattle.
The Giants couldn't score on their four power plays and Seattle went 2 for 3 with the man advantage.
Benson put away the winner with 3:42 left to play.
BLAZERS 3 AMERICANS 0
KAMLOOPS, B.C. — Connor Ingram made 30 saves as the Blazers shut out Tri-City.
Deven Sideroff, Cole Ully and Collin Shirley supplied the offence for Kamloops (21-29-6).
Eric Comrie stopped 34 shots for the Americans (25-26-3).
ROCKETS 5 COUGARS 2
KELOWNA, B.C. — Dillon Dube scored twice as the Rockets flew past Prince George.
Josh Morrissey had the eventual winner at the 8:21 mark of the second period for Kelowna (42-8-4), while Cole Linaker and Rourke Chartier also scored.
Chase Witala and Jari Erricson replied for the Cougars (21-32-3).
ROYALS 2 OIL KINGS 1
VICTORIA — Austin Carroll's second period goal was the eventual winner as the Royals edged Edmonton.
Jack Palmer gave Victoria (30-20-4) a 1-0 lead in the first period.
Mads Eller tied it in the second period for the Oil Kings (25-25-6).