Another summer of European qualifiers is doing nothing to slow KuPS' domestic form, they secured their sixth win in a row in the league, while Gnistan remain fourth for now after their three-game winning run came to an end.
The only goal arrived with just 100 seconds played - Saku Heiskanen played a low ball into the box that was missed by almost everyone - including the committed Oskar Lyberopoulos in goal - but not by Saku Savolainen at the back post, who tapped the ball into the empty net.
The home side created plenty in response and managed to stay in the game with some last-ditch defending, but they could not find a way past Hemmo Riihimaki in the KuPS goal, as he made eight saves to take his side eight points clear at the top.
Mariehamn finally ended their long losing run with a point against AC Oulu last time out, but it was business as usual for the winless side as they were comfortably beaten by TPS Turku, who ended a two-game losing streak.
Kian Visser connected well with a low Nikolas Talo to put the hosts ahead in the 20th minutes, before Samuel Anini cut inside and struck the ball in at the near post just before the break. 10 minutes after which, Visser added his second and TPS' third by heading in Elmer Vauhkonen's cross.
TPS stay eighth but are within touching distance of sixth-placed Oulu, who do have a game in hand. Mariehamn stay on five points, nine behind SJK.
Lahti are also two points shy of Oulu but remain above TPS on goal difference after returning to winning ways against Jaro, whose place in the Relegation Group is all but confirmed as they sit 12 points off sixth with four matches to go.
The home side scored with nine minutes gone and nine minutes to go - Mamodou Sarr stooped very low to reach and turn in Romain Sans' cross, then, Justus Ojanen secured the points following a link-up with Neemias. It's a first loss in four for Jaro, while it's four wins in five and just one defeat in seven for Lahti.
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