After scoring five times in the opening 20 minutes and romping to an 8-1 win at home in game three, KalPa went on the offensive again, but this time were finding the SaiPa defence much tougher to break down.
Kari Piiroinen was pulled early in the previous match, but he made six saves in the first period last night, including crucial stops when SaiPa were a man down after a high sticking call against Otto Kivenmaki.
But the home defence eventually caved in the seventh minute of the second period, and were unable to survive a second KalPa powerplay after Samuli Niinisaari was sent to the box for holding.
The visitors worked the puck around the attacking zone, before Jesper Mattila found Kasper Simontaival, who was looking to pick out a pass, but when nothing was on, picked out the smallest gap between Piiroinen and the top corner of the goal to put his side in front.
Approaching the final five minutes of the second, KalPa soaked up SaiPa pressure and broke out of their defensive zone, finding Andreas Okany on the left wing.
Okany passed inside to Simontaival, who was on hand to power the puck past the goaltender and finish off a well-worked counter attack.
KalPa had their backs to the wall throughout the third period, facing wave upon wave of SaiPa attack as the hosts took a total of 15 shots to KalPa's two.
But the Lappeenranta side could not find a way through visiting goaltender Stefanos Lekkas, who made nine of his 16 total saves in the third period alone to secure the 2-0 win.
One could hear a pin drop in the Lappeenrannan jaahalli when the final horn sounded - the home crowd knew all too well their side must now win twice away and once at home against a side who has just done the same to them.
KalPa were in no mood to celebrate early; their first chance to get the series won and start the party will come in Kuopio tomorrow.