Four points shy of the championship group places with two games to play, defeat would see Lahti join SJK in the relegation group in September, yet a first win in three keeps their European ambitions alive for the time being.
But they did it the hard way, as two bookings 10 minutes apart saw Jose Muller dismissed with a little over half an hour gone, and early in the second half, the extra man paid dividends for the hosts, who took the lead when a low ball fizzed across the face of goal to Jaakko Moisio, who pulled it back for Eze Onuoha to bundle in.
The visitors didn't let their heads drop, and managed to level 10 minutes from time when Romaric Yapi set up Yohan Cassubie, and within seconds of the restart, the tide continued to turn in Lahti's favour, when SJK's Kelvin Pires received his second booking of the second half, and with it, his marching orders.
With all the momentum, the away side managed a grab an unlikely victory deep into added time, as the Seinajoki side gave Yapi time and space to slot and simple through ball to Aaron Lindholm, who coolly rolled the 95th-minute winner into the bottom corner.
Lahti are a point behind both VPS and AC Oulu, who have a chance to move four clear again later this round. In fourth place, Gnistan need just a point from their final two games to stay out of Lahti's reach. SJK lose for the second game in a row, though even victory would have seen them stay in 10th place.
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