Brilliant Billy Godleman hit a third successive Royal London one-day Cup century as Derbyshire, chasing a revised target of 225 in 22 overs, and Yorkshire tied a thriller at Emerald Headingley.
Godleman became the first Derbyshire batsman to score three successive List A centuries.
A near three-and-a-half-hour afternoon rain delay meant Derbyshire, needing 17 off the last over and two off the last ball, were faced with a stiff target following early fireworks from the hosts, who posted 308 for two in 40 overs.
David Willey bowled the last over, with Godleman and Matt Critchley running a bye to the wicketkeeper off the last ball as Yorkshire tied their second game in their last three North Group outings.
Yorkshire would have surely surpassed their highest List A total of 411 for six but for rain.
Derbyshire then slipped to 10 for two in reply before captain Godleman and South African Leus du Plooy changed the game with a dynamic 135 partnership inside 13 overs.
Du Plooy hit five sixes in 75 off 37 balls before falling, only for Godleman to back up previous competition scores of 87, 116 and 106 by reaching his latest ton off 59 balls in the last over.
He finished with 107 not out off 62, including six sixes.
Yorkshire have now won one, tied two and lost one of their first four North Group matches, while Derbyshire have won two, lost one and tied one in the race for a top three finish.
Each of the Vikings top four, Tom Kohler-Cadmore, Adam Lyth, Harry Brook and departing England limited overs international Willey, all posted half-centuries after the hosts elected to bat.
Kohler-Cadmore top-scored with 79 off 92 balls and Lyth hit two sixes in 78 off 60.
The opening pair shared 157 inside 24 overs to give their side the ideal platform on an excellent pitch.
Lyth was first to go, top-edging a pull at Ravi Rampaul to Sam Conners running in from long-leg.
Conners had earlier struck Lyth on the head with a bouncer.
Kohler-Cadmore had hit a similarly measured 97 in Sunday’s thrilling Roses defeat, but he missed out on a century again when he slapped Critchley’s leg-spin to extra cover, leaving the Vikings at 167 for two in the 27th.
Then came the fireworks, led initially by Willey, who will link up with England for a training camp this weekend before the World Cup.
Willey smashed three of six sixes in the Vikings innings and reached 50 off 39 balls before finishing with 72 not out off 49.
Unbeaten Brook, 59 off 40, reached his half-century off 36, the 20-year-old backing up an opening round century in victory over Leicestershire.
Willey and Brook had shared 141 inside 14 overs for the third wicket - a Yorkshire record for that wicket in matches against Derbyshire - when the rain arrived, with 113 of those coming in what turned out to be the final eight overs of their innings.
Lyth’s off-spin then accounted for Luis Reece, stumped, before Willey had Wayne Madsen caught at deep square-leg.
But then came the stunning turnaround, as Godleman and du Plooy targeted the leg-side with great success against an off colour home attack who regained composure just in time thanks to tight overs at the death from Willey, Duanne Olivier and Steve Patterson.
Godleman reached 50 off 28 balls after du Plooy’s had come off 24.
The latter holed out to Lyth, leaving the score at 145 for three in the 15th over, only for Critchley to help Godleman set up the mayhem at the death.