2-1 and 7-2 wins had eaten into the overall advantage of Farjestad, who just needed one victory to reach the semi-finals.
The same was therefore true today, but despite a pair of powerplay opportunities, the home side failed to break the deadlock in a goalless first period in which they had 12 shots on goal to Rogle's five.
Rogle punished them, and then some, in the first seven minutes of the second period, which was a minute old when Calle Sjalin's effort off target was picked up behind the net by Fredrik Olofsson, who knocked it back for Felix Nilsson to finish from close range.
Three minutes later, the visitors won a face-off in their own zone before Leon Bristedt and Daniel Zaar launched a counter-attack which was coolly finished off by the arriving Albin Sundsvik.
Another three minutes went by before the Angelholm side added another - this time Sundsvik and Sjalin combined to set up Zaar to make it 3-0. It could have been worse for FBK come the midpoint, but Olofsson had a goal disallowed for obstruction on the goaltender.
Credit to Farjestad, they fought back hard in the third period - just over a minute in, Viktor Lodin had the sense to tap the puck back away from a congested centre for Radim Zohorna to cut the deficit to two, before Lodin himself scored the home side's second with 16 minutes still to play.
However, those were 16 minutes in which Rogle held out, limiting the Karlstad side to 10 shots on goal in the final period in total, and taking the 3-2 win that sets up a deciding match back in Angelholm on Sunday 5th April.