David Willey came back to haunt the Steelbacks once again as Yorkshire Vikings claimed a crushing victory at Headingley.
Willey, who shone when Northants won the T20 tournament in 2013, was brilliant with the ball, finishing with figures of four for 18 from his four overs.
Tim Bresnan and Jack Shutt took two wickets apiece as the Steelbacks slumped to 107 all out in 18 overs, losing by a massive 80 runs.
Only Tom Sole had any sort of joy with the bat as he made an unbeaten 41 from 35 balls.
But it was a huge defeat for Northants, who lost the toss and allowed Yorkshire to make 187 for seven.
Graeme White (2-18), Faheem Ashraf (2-34) and Rob Keogh (2-38) were in the wickets, but the Vikings set a sizeable total thanks to openers Tom Kohler-Cadmore (51) and Adam Lyth (50).
Northants had headed into the game knowing they would not be able to quality from the Vitality T20 Blast North Group following the abandonment of Worcestershire's clash with Nottinghamshire on Wednesday.
That meant Worcestershire took the point they needed to claim the fourth and final qualification spot in the north.
And Northants will now complete this season's T20 campaign at home to Worcestershire on Friday (start time 6.30pm).
Yorkshire Vikings: Lyth (c), Kohler-Cadmore, Willey, Brook, Tattersall (wk), Leaning, Fraine, Bresnan, Thompson, Maharaj, Shutt.
Steelbacks: Levi, Rossington (wk), Cobb (c), Pretorius, Wakely, Keogh, Ashraf, Sole, White, Buck, Muzarabani.