Derbyshire 184 for 5 (Godleman 67, Madsen 47, Wilson 33*, Patterson 3-37) beat Yorkshire 180 for 5 (Sarfraz 42, Lyth 34) by five wickets
Billy Godleman's second half-century of this season's NatWest T20 Blast helped Derbyshire to the top of the North Group with a five-wicket win over Yorkshire at Headingley.
Godleman led the pursuit of 181 as the Falcons secured the double over Yorkshire, winning with two balls to spare.
The opener hit 67 off 48 balls after Pakistan captain Sarfraz Ahmed scored 42 of Yorkshire's 180 for 5 on his debut.
Derbyshire, who have never reached Finals Day, leapfrogged Birmingham due to a better net run-rate, while Yorkshire are still on course for qualification despite a first Blast defeat in 11 matches at Headingley.
Yorkshire's innings lacked the fireworks of previous efforts, with them posting over 220 three times this season. They reached 54 for 1 after six overs having elected to bat, losing Tom Kohler-Cadmore for a brisk 29 with two leg-side sixes.
David Willey and Adam Lyth, who hit 34, fell in the space of four balls in the ninth and 10 overs to spinners Wayne Madsen and Imran Tahir, leaving the score at 81 for 3.
Madsen was the pick of the Falcons bowlers with 1 for 29 from his four overs and later hit a crucial 47 with the bat.
Sarfraz and Shaun Marsh shared 67 inside nine overs for the fourth wicket before Hardus Viljoen struck twice in four balls, bowling Sarfraz as he looked to give himself room to slash over cover and Jack Leaning to leave the score 154 for 5.
Marsh later did not field due to concussion having been hit by a Matt Henry slower ball bouncer whilst batting. He complained of dizziness when warming up before Derbyshire's chase and Martyn Moxon, Yorkshire's director of cricket, said he would probably be out for at least a week, missing the next T20 against Durham and the Championship match against Essex.
Derbyshire debutant Tom Wood skied Bresnan to midwicket in the fourth over of the chase before Luis Reece was caught at short third-man trying to scoop Steve Patterson as the score fell to 46 for 2 in the sixth.
With rain coming and going, all eyes were on Duckworth-Lewis-Stern, but the visitors kept their noses in front thanks to Godleman.
He reached his latest half-century off 33 balls in the 10th over, by which stage the score had reached 83 for 2.
Godleman found an aide in in-form Madsen. They shared 77 inside eight overs for the third wicket before former was caught behind off Willey as the score fell to 123 for three in the 14th.
Steven Patterson and Adil Rashid tightened things up as the target became 49 off five overs and 33 off three.
Madsen and Henry fell to Patterson in the 19th before Alex Hughes, with 10 needed off the last, smashed the first ball from Bresnan for six before captain Gary Wilson hit the winning runs.