A fighting lower order display by Fleetwood combined with the elements scuppered Lancaster’s chances of 15 points on Saturday.
Adam Sharrocks’ unbeaten 39 took the hosts from a precarious 151-8 to victory in the final over.
Earlier in the day Fleetwood skipper Matt Clark inserted Lancaster with Jamie Heywood (35) and Alex Metcalfe (46) putting on 90 at the top of the order. But from there Lancaster entered into a familiar stumble.
At 100-4 Lancaster looked to be letting their position of strength slip but Rameez Raja applied himself in difficult conditions.
The Pakistani professional finished eight short of a half century as Lancaster were ultimately bowled out for 185.
In reply, league top scorer David King helped Fleetwood past 50 in good time.
Ben Simm was in fine form however, removing Adam Parker, Tom Wilson and Dean Bell before Iain Burstow got in on the act to send James Wilson packing.
Simm then got King, trapping the Australian in front for 67 to give the visitors the upper hand.
The rain then began to fall and mistakes crept into Lancaster’s fielding but as the runs required went below 50 Burstow took two wickets in two balls.
His fourth then meant the score was 151-8 but as the rain got heavier the game began to slip from the Lune Road men’s grasp.
Sharrocks and Matt Clark took full toll on loose deliveries as Lancaster’s two off-spinners struggled to get a grip on the ball.
With four required from the final over, Sharrocks’ fine innings was capped off with a lofted boundary to leave Lancaster rueing another missed opportunity for points.