Bartosak stopped all 20 shots he faced as Red Deer shut out the Edmonton Oil Kings 5-0 on Sunday.
The win sets up a tie-breaker game between the Rebels and the Prince Albert Raiders that will be played in Red Deer, Alta., on Tuesday. Red Deer and Prince Albert finished the regular season in a tie for eighth with 75 points each.
The winner of that game will face the top-seeded Oil Kings in the first round of the WHL's Eastern Conference playoffs in Edmonton on Saturday.
Rhyse Dieno scored and added two assists for the Rebels (35-32-5), while Adam Musil, Scott Feser, Wyatt Johnson and Haydn Fleury chipped in as well.
Tyler Santos made 33 saves for the Oil Kings (50-19-3).
TIGERS 6 HURRICANES 2
LETHBRIDGE, Alta. — Miles Koules had the eventual winner as Medicine Hat rolled past the Hurricanes.
Captain Curtis Valk, Chad Butcher, Cole Sanford, Jacob Doty and Connor Hobbs rounded out the offence for the Tigers (44-24-4). Nick Schneider made 24 saves.
Brady Ramsay and Riley Sheen replied for Lethbridge (12-55-5) who end the season on a 14-game losing skid.
Hurricanes goalie Stuart Skinner stopped 27 shots.
WINTERHAWKS 5 SILVERTIPS 4 (SO)
PORTLAND, Ore. — Derrick Pouliot and Nicolas Petan scored in a shootout to lift the Winterhawks over Everett.
Taylor Leier scored two for the U.S. Division-leading Portland (54-13-5), including the game-tying goal while short-handed at 8:13 of the third period. Petan scored in regulation and added an assist, and Alex Schoenborn rounded out the Winterhawks offence.
Joshua Winquist had two goals for the Silvertips (39-23-10), while Matt Pufahl and Dawson Leedahl also scored.
Portland's Adin Hill stopped 17 shots through overtime. Austin Lotz started in net for the Silvertips but left the game after giving up two goals on 12 shots, and Carter Hart stopped 30 of 32 shots in relief.
THUNDERBIRDS 6 AMERICANS 1
KENNEWICK, Wash. — Shea Theodore scored two goals and helped on another as the Thunderbirds dominated Tri-City.
Branden Troock, Mitch Elliot, and Alexander Delnov each had a goal and an assist apiece, and Justin Hickman also scored for Seattle (41-25-6).
Morgan Geekie was the lone goal scorer for the Americans (29-33-10), who end the season with two wins in their last 10 games.
Thunderbirds netminder Taran Kozun stopped 18 shots for the win, while Tri-City's Evan Sarthou made 24 saves in the losing effort.