Durham 193 for 4 (Clark 53, Neesham 42*, O'Rourke 3-37) beat Yorkshire 130 (Lyth 38, Potts 2-22, Sowter 2-22, Neesham 2-23) by 63 runs
Durham claimed their second Vitality Blast win over Yorkshire in six days as they strengthened their position inside the North Group's top four places with a comprehensive victory at the Banks Homes Riverside.
With this 63-run success, Durham's fifth in eight matches, they all but ended Yorkshire's chances of reaching the quarter-finals. This was their sixth defeat in eight as they failed to chase 194.
Durham's 193 for 4 included a series of dynamic contributions, led by opener
Graham Clark's 53 off 35 balls. New Zealand allrounder
Jimmy Neesham also starred with 42 not out off 21 before striking twice with the ball in defence.
Yorkshire's forlorn chase continued through a ground power-cut, and they were bowled out for 130 inside 18 overs. Opener Adam Lyth top-scored with 38.
Durham beat Yorkshire at York on Sunday, a game in which England seamer Matthew Potts starred with 5 for 17.
Yorkshire started tidily in this return fixture, conceding only seven in the first two overs having elected to bowl. But Durham hit back courtesy of their captain, Alex Lees.
He clattered four fours in five balls - strong on the pull - as 17 runs came off Will O'Rourke in the third over, the hosts going on to reach 50 without loss from five overs. Lees edged the same bowler behind in the sixth over, falling for 40 off 24 balls.
Every Durham batter aside from Ben McKinney, who made 5 before top-edging behind off Jafer Chohan, got set and contributed.
Chief among them were Lees, fellow opener Clark and experienced Neesham, who crashed two sixes in his late assault, including a huge heave over midwicket off fellow Kiwi O'Rourke.
Clark started the 13th over by muscling back-to-back sixes down the ground off Chohan's leg-spin before reaching his fifty off 30 balls later in the over.
Having shared 56 with Lees, Clark added a third-wicket 62 with Colin Ackermann, 28, before both holed out to O'Rourke in the 15th over.
Neesham then ended with a bang to give Yorkshire a sizeable task in reply.
The visitors started well with the bat, captain Dawid Malan hoisting a six over midwicket off Callum Parkinson's spin as 24 came from the first two overs.
Malan, on 21, was bowled by Potts with the score on 42 in the fifth over.
The brief power cut didn't stop play despite no floodlights or scoreboard, and it also seemed as if Yorkshire's power was cut as the score reached 74 for 3 after 10 overs, with 120 more needed.
Jonny Bairstow was bowled for 19 as he tried to attack Nathan Sowter's leg-spin before Will Luxton dragged left-armer Parkinson to long-on.
And when Lyth was run out backing up by Parkinson following a fierce Will Sutherland drive, Yorkshire were 91 for 5 in the 12th over and under severe pressure.
It was quickly evident that their task was too tall, and with it surely went their hopes of quarter-final qualification.
Sowter struck again to remove Jordan Thompson shortly afterwards before Neesham's seam - 2 for 23 from three overs - ousted Sutherland and Chohan as the White Rose subsided.