Skellefteå's Linus Söderström has kept a clean sheet in the last two games against Rögle.
In the fourth quarter-final meeting, he was relegated to the bench and Skellefteå conceded five goals and lost.
The Scanians won 5–2 at home and tied the match series at 2–2.
Adam Engström gave Rögle the lead in the first period, but just over a minute later, Skellefteå's equalizer came at 1-1 through Måns Forsfjäll.
Skellefteå also equalized shortly after Stål-Lyrenäs' 2-1 goal in the middle of the second period, this time through Oscar Möller.
But AIK did not manage to pull level a third time, and Rögle finally won 5–2, scoring two goals into an empty net as Skellefteå strived for a leveller, and evened the match series at 2-2.
The fifth match between the teams will be played in Skellefteå on Friday.