A superb maiden one-day century by Northamptonshire Steelbacks captain Alex Wakely spearheaded a 29-run win against Kent Spitfires at Tunbridge Wells in Group A of the Yorkshire Bank 40.
There was also a fine 88 from Northants opener Rob Newton, who added 144 in 18 overs with Wakely before he was forced to retire hurt due to an ankle injury.
Northants, asked to bat first, totalled 263 for four and then bowled with great discipline to restrict Kent to 234 all out in reply on a fast-scoring ground.
Trent Copeland finished with 4-46 while Lee Daggett was particularly outstanding as he took 2-28 from his eight-over allocation.
Kent were 132 for one in the 24th over before a mid-innings collapse to 149 for five left them with too much to do in the last 10 overs.
Alex Blake did his best to revive the innings by hitting 43 from just 24 balls, including a six and seven fours, But, when he sliced a catch to cover off Copeland in the third of the four batting powerplay overs, there were only a few more defiant blows from Matt Coles before Northants’ victory was confirmed.
This was Kent's third defeat in seven games in the competition and - despite being second in the table, a place ahead of Northants - they will now struggle to qualify as leaders Nottinghamshire Outlaws already have five wins from five games and are odds-on favourites to finish top later in the season.
Wakely's 102 came from just 77 balls, with four sixes and seven fours, and he provided the major impetus with a stream of fine strokes, including three extra-cover boundaries in a single over from off-spinner Adam Riley.
Newton was never as fluent, as his 88 took 103 balls, but struck two sixes and eight fours in all and was just beginning to put real pressure on Kent's bowlers when, in the 35th over, he suffered the injury to his right ankle in freakish fashion.
Going down on one knee, Newton badly twisted his ankle as he flipped a ball over his left shoulder to the fine-leg boundary for his eighth four.
After contorting himself to pull off the stroke against left-arm seamer Adam Ball, Newton crumpled in pain in the crease and could only continue after receiving treatment as he lay on the pitch.
He straight-drove Ball's next delivery over long-off for six, but flinched with pain again as he played the shot and had to hobble from the field.
Wakely completed his brilliant hundred at the start of the last over, lofting Calum Haggett over mid-off for four, but then skied a catch from the next ball after Northants had also lost David Willey to a mishit to deep cover off Coles.
For Kent, Haggett and Coles bowled excellently with the new ball and Darren Stevens was his usual metronomic self with his medium-paced swing and cut.
Riley, apart from one expensive over, was tidy but Ball did not look comfortable in the batting powerplay overs and Kent clearly missed their captain James Tredwell, away with England's one-day international team, and the injured seamer Mark Davies.
Northants bowled and fielded better than Kent as a unit, with Stevens run out for 10 by an excellent pick up and throw from Mohammad Azhar Ullah coming in from long-leg, and - as in their previous defeat at Sussex - Kent seemed to get themselves in a tangle with their choice of batting order after a good start.
Sam Northeast, with 41 from 51 balls, added 64 for the first wicket alongside Sam Billings, who went on to 57 from 67 deliveries as he put on a further 68 for the second wicket with Brendan Nash.
But when Nash skied a catch on 32 and Billings was bowled swinging at Daggett, the innings lost momentum at a crucial stage as Northants seized their chance.