The Steelbacks beat the weather but not Lancashire Lightning as the Vitality T20 Blast North Group table-toppers took the points at the County Ground on Wednesday night.
Following an afternoon that saw plenty of rainfall, the Northants ground staff did superbly to get the game on, giving their team a chance to record a much-needed victory.
But after losing the toss, the Steelbacks were restricted to 157 for seven, with Adam Rossington (40) and Dwaine Pretorius (38) the stand-out performers.
And Lancashire made light work of the reply, with Alex Davies delivering an unbeaten 75 as the away side won by eight wickets.
It means eighth-placed Northants remain in danger of failing to make the quarter-finals as they are still two points adrift of the fourth qualification place with five games to play.
Their next match is also at home, against Leicestershire Foxes on Friday night, and David Ripley's men will be desperate for a win in a hugely competitive tournament.
They did have high hopes before facing Lancashire thanks to an uplift in form that saw them beat Durham and almost defeat Leicestershire, only to be denied by the weather.
And the Steelbacks started well against Lancashire, who were without key man Glenn Maxwell, who failed a late fitness test.
Richard Levi and Rossington looked in control from the off as they helped Northants to reach 33 without loss after 3.3 overs.
But Levi then went for 18 as he was caught at third man off the bowling of Australian ace James Faulkner.
Josh Cobb again came to the crease earlier than he would have liked, but he didn't stick around for long as, after facing five balls without scoring, he was dismissed from the sixth.
Saqib Mahmood was the man who got the wicket thanks to a miscue from Cobb, who was caught on the square leg boundary by Davies.
Rossington continued to play nicely until he was removed by Liam Livingstone for 40 from 32 balls, leaving the Steelbacks, who had rebuilt well, on 83 for three.
Lancashire then started to turn the screw with their spin, and Alex Wakely was stumped after being deceived by a Livingstone delivery.
At 91 for four, Northants needed a partnership, and they got a productive one from Rob Keogh and Dwaine Pretorius, the latter striking the ball superbly.
Pretorius was eventually dismissed when Matt Parkinson returned for his final over, removing the South African for 38.
Keogh carried on to finish unbeaten on 27, but Faheem Ashraf and Luke Procter were both dismissed by Faulkner in the last over of the innings.
Lancashire were in a hurry at the start of their reply as Davies and Livingstone took the bowlers to task.
That was until Cobb brought himself on and got the breakthrough, with Livingstone's ambition eventually costing him as he was caught by Keogh for 22.
But Lancashire continued in serene fashion before Ashraf returned, and the Pakistan pace man bowled Steven Croft for 27.
That left Lancashire needing 54 runs from 43 balls with eight wickets remaining, and the Steelbacks simply had to squeeze their opponents.
But Lightning would not let them have it their own way as the impressive Davies just kept pushing on, alongside Dane Vilas.
And the men in red eventually reached their victory target of 158 with nine balls to spare.
Steelbacks: Levi, Rossington (wk), Cobb (c), Wakely, Pretorius, Keogh, Ashraf, White, Procter, Buck, Sanderson.
Lancashire Lightning: Davies, Livingstone, Croft, Jennings, Lamb, Vilas (c, wk), Faulkner, Bohannon, Mahmood, Gleeson, Parkinson.