Northamptonshire 183 for 2 (Gay 84*) beat Derbyshire 177 for 9 (Hudson-Prentice 64, White 4-20, Sanderson 3-29) by eight wickets
Emilio Gay's unbeaten 84 led Northamptonshire to an eight-wicket victory over Derbyshire, securing their first win of the Royal London Cup campaign.
The academy graduate saw the hosts over the line with three balls to spare in their chase for 178 for victory in a game reduced to 28 overs-a-side by morning rain.
The left-hander's heroics came after the Steelbacks' new-ball pairing of Curtley-Jack White and Ben Sanderson had taken 4 for 20 and 3 for 29 respectively, reducing Derbyshire to 8 for 4 before Fynn Hudson-Prentice's swashbuckling 64 gave the still winless visitors something to defend.
Derbyshire's batting woes this season have been well documented, and they were in trouble from the very first ball when White's lbw appeal against Mitch Wagstaff was upheld.
Sanderson's first over brought greater carnage. Harry Came tried to hit the Steelbacks' seamer over the top, only for Rob Keogh to pull off a stunning catch running back from mid-off.
The next ball ripped out Tom Wood's off-stump and although Alex Hughes survived the hat-trick, it was three in four for Sanderson when the Derbyshire skipper gloved one banged in short through to wicketkeeper Vasconcelos.
The visitors were in disarray, but Hudson-Prentice led a thrilling counter offensive, hooking Wayne Parnell for a huge six.
The all-rounder took three fours in an over from Freddie Heldreich and when the in-form Tom Taylor came on to try and halt the onslaught he too was hit for six over mid-on before Hudson-Prentice smote three fours back over the bowler's head.
His 50 came off 37 balls before he took one swing too many at Graeme White and lost his off-stump, ending a fifth wicket stand of 106 with Brook Guest (45) who proved a perfect foil.
Another collapse followed as Anuj Dal, Alex Thomson and Guest were sent packing in rapid succession by Curtley-Jack White, but some late blows by Nils Priestley in a cameo of 25 gave Derbyshire hope.
Vasconcelos and Gay began steadily, the latter the more fluent, striking Dal back over his head for four as 50 came up in the ninth over.
Derbyshire fielded tigerishly pulling several shots back from the ropes, but the openers continued to accumulate and keep their side well up with the rate.
The hundred came up in the 16th over with Gay first to 50 from 41 balls with four fours, Vasconcelos (50) reaching his half-century soon afterwards with the help of six boundaries, before the Northamptonshire skipper skied one to deep mid-off off Thomson, ending the stand at 105.
Ben Curran made only 12 and 27 were needed from the last three overs, but Keogh's 33 from 16 balls including two huge sixes settled matters.