Gerlach’s goal came with one second left on a 5-on-3 power play after the Warriors took back-to-back delay of game penalties.
Kyle Crnkovic and Kirby Dach also scored for the Blades, who hold a commanding 3-0 lead in their Eastern Conference quarter-final match-up.
Nolan Maier made 22 saves for the win.
Keenan Taphorn and Carson Denomie scored for the Warriors.
Adam Evanoff had a busy night in net, stopping 37 of the 40 shots he faced.
The Blades can wrap up the first-round series when the teams meet Wednesday in Moose Jaw.