Penner's goal two minutes into OT came after the Tigers (39-22-3) tied the game on third-period goals by Chad Butcher and Curtis Valk.
Valk finished with two goals while Marek Langhamer did his part with 38 saves.
Edgars Kulda, with a short-handed goal, Reid Petryk and Brett Pollock scored for the Eastern Conference-leading Oil Kings (44-15-3), and Tristan Jarry made 32 saves.
WHEAT KINGS 6 HURRICANES 2
BRANDON, Alta. — Curtis Honey stopped 36 shots and the Wheat Kings offence did the rest against league-worst Lethbridge.
Jayce Hawryluk scored twice for Brandon (30-26-8), while Eric Roy, Rene Hunter, Rihards Bukarts and Jens Meilleur also scored.
Tyler Wong and Carter Fong had a goal each for the Hurricanes (12-48-5), who have lost seven in a row.
Lethbridge goaltender Jonny Hogue did what he could, making 40 saves.
BRONCOS 6 PATS 2
SWIFT CURRENT, Sask. — The Broncos scored the first five goals of the game to overwhelm Regina.
Jake DeBrusk scored twice for Swift Current (31-24-8), which also got goals from Colby Cave, Jay Merkley, Glenn Gawdin and Coda Gordon.
Braden Christoffer and Kyle Burroughs scored for the Pats (35-23-6).
Eetu Laurikainen turned aside 27 shots for Swift Current. Daniel Wapple and Dawson MacAuley meanwhile gave up three goals each in net for Regina.
ICE 5 WARRIORS 1
MOOSE JAW, Sask. — Kootenay broke a tie with a four-goal outburst in the third period to charge past the Warriors.
Tim Bozon and Sam Reinhart each scored twice for the Ice (36-23-4), while Jaedon Descheneau added a single.
Jesse Forsberg had the lone goal for Moose Jaw (16-38-9).
Mackenzie Skapski finished with 22 saves for the Ice. Warriors goalie Zach Sawchenko was far busier, stopping 37 shots.
REBELS 2 BLAZERS 0
RED DEER, Alta. — Patrik Bartosak stopped 32 saves as the Rebels shut out Kamloops.
Vukie Mpofu and Rhyse Dieno scored for Red Deer (30-30-4) in the first period.
Bartosak took over from there and was effective in the second when Kamloops (13-46-5) outshot the Rebels 18-7.
Bolton Pouliot meanwhile finished with 34 saves for the Blazers.
SILVERTIPS 5 RAIDERS 1
EVERETT, Wash. — The Silvertips exploded for five unanswered goals to crush Prince Albert.
Noah Juulsen, Patrick Bajkov, Brayden Low, Kohl Bauml and Joshua Winquist scored for Everett (30-23-9).
Shane Danyluk opened the scoring for the Raiders (29-29-5) 4:58 into the game before the Silvertips went on their run.
Austin Lotz needed to make just 18 saves for Everett, while Cole Cheveldave stopped 25 for the Raiders.
ROCKETS 4 AMERICANS 3 (SO)
KENNEWICK, Wash. — Myles Bell scored shorthanded then had the only goal in the shootout as the league-leading Rockets survived against Tri-City.
Marek Tvrdon scored twice for Kelowna (50-9-4), which led 2-0 after the first period but fell behind 3-2 before Tvrdon tied the game in the third.
Michal Plutnar, Beau McCue and Brian Williams each scored for the Americans (27-28-8).
Jackson Whistle stopped 25 shots for Kelowna. At the other end of the ice, Eric Comrie made 39 saves.