Northern’s game management was the key to their win at Preston Avenue coupled with a lack lustre performance by the home side.
The visitors seemed to want the win more and Park looked sluggish at times, although they started brightly as Northern kicked off with the wind and slope advantage.
For the first four minutes Percy Park took the play to the visiting side and should have scored, but canny play by one or two of the Northern forwards slowed ball down enough to deny the try, but Park did come away with three points when Michael Grove kicked a penalty.
Ex Sheffield fly-half Donal Collins kicked well, pinning Park back after several attacks were repelled.
There were good breaks in midfield by Ricki Hasnip and John Scott but the support play was not on hand and scoring opportunities went begging.
The best chance came as Josh Hedley made a break for the line but was tackle short and Park could not gather up the loose ball to capitalise.
Northern levelled the scores with a Collins penalty on 16 minutes and then two minutes later it was the Northern fly-half who set play going from his own 22, feeding James Crowther who broke through a tackle and made 25 yards before passing inside.
The ball went loose but was picked up and a play involving half of the Northern pack saw hooker Henderson pop the ball inside to Kay who found Ludford and his pass five metres out gave lock Dave Snoddin the opportunity to dive over for the try.
The conversion gave the McCracken Park side a 10-3 lead which they held until the half-time break.
Percy Park kicked off the second period but within two minutes were further behind. They were penalised for feeding at the scrum and a quick tap from the free kick found centre Chris Hood who chipped the on coming defence. The hosts seemed to have the ball covered but indecision allowed Hood to gather the ball short of the try line and dive over in one movement for the score for a 17-3 lead.
Northern were repeatedly penalised for a number of infringements as Park looked to cut the deficit and eventually scrum-half Jimmy Baldwin broke through the defence finding full back Michael Grove on hand for the try as Sean Williamson popped the ball up from the back of a scum. Michael Grove kicked the conversion.
Collins and Grove exchanged penalty kicks for 13-20 and then on 74 minutes Collins kicked a drop goal to take his side ten points clear.
Park continued the attack and again Northern conceded penalty after penalty before one of their players was eventually binned.
Park opted for a scrum close to the Northern line, and Ethan Wilson who had switched from centre to number 8, went over in the 82nd minute to secure a losing bonus point.
Northern deserved their win, the first against Park for some years.
There are no games next week with the World Cup final taking place.