Middlesex Panthers were dominant with the bat to record an emphatic win over Sussex Sharks to climb above their opponents in the South group standings.
Dawid Malan hit an unbeaten 115, while Paul Stirling added 88 as the duo put on an opening stand of 187, although Eoin Morgan was out for a golden duck.
Sussex battled hard to keep the run rate up to give themselves a chance of making their 222-run target, led by Luke Wright with 91, but Kyle Abbot claimed figures of 5-14 to ensure that the hosts could not match Middlesex's total.
Durham Jets survived a late surge from Yorkshire Vikings to inflict a first defeat of the season on the visitors.
Durham split the workload with the bat, with Phil Mustard, Paul Collingwood, Gordon Muchall and John Hastings all passing the 30-run mark
Yorkshire still needed 22 with just seven balls remaining after Keaton Jennings had ripped through the middle order, but Tim Bresnan and Adil Rashid fell just short as they went for broke off the last over.
Birmingham Bears needed four runs off the final ball to secure a closely-fought win over Northamptonshire, leaving their opponents still looking for their first win of the season.
Richard Levi hit a half-century to get the home side off to a bright start, but Josh Cobb was the only other batsman to reach 20 for Northamptonshire.
Muhammad Azharullah gave the side a chance, taking three wickets in quick succession to limit Birmingham's reply, but Will Porterfield helped the defending champions draw the scores level in the final over.
Porterfield was on strike for the final ball, but byes from Azharullah's delivery handed the Bears the last-gasp win.
Derbyshire Falcons reached their target with 16 balls remaining to secure a victory over Lancashire Lightning.
Lancashire recovered from 28-3 as Alex Davies hit 41, while Paul Horton added a knock of 20, but the visitors could only post a total of 127.
Hashim Amla and Tillakaratne Dilshan ensured that Derbyshire started their reply well, adding 93 for the opening wicket before Amla fell for 51.
Dilshan was run out soon after for 38, but Chesney Hughes quickly secured the necessary runs to wrap up the victory.
Sam Northeast fell just short of a century to lead Kent Spitfires to a comfortable win over Surrey, hitting 96 off just 47 balls.
The captain led the home side to a score of 193 off their 20 overs before Moises Henriques and Kumar Sangakkara got Surrey off to a strong start in their reply, but neither remained at the crease long enough to complete the chase.
Worcestershire Rapids restricted Leicestershire Foxes to a low score on their way to their first win of the campaign.
Only Grant Elliott managed more than 30 for the visitors, allowing Daryl Mitchell to lead the Worcestershire run chase with 58, before Ross Whiteley hit the winning runs with almost three overs to spare.
Glamorgan fell short in their quest for a second win of the season as they were well beaten by Hampshire.
After winning the toss and choosing to bowl first, Glamorgan restricted their opponents to 148, led by Sean Ervine with 49.
Kyle Hogg and Michael Hogan led the attack, each claiming four wickets for the home side, but the top-order batsmen fell short as Glamorgan were quickly reduced to 13-3 in their reply.
Somerset picked up their first win of the season though, edging out Essex Eagles after surviving a run out appeal on the final ball of the match.
Jesse Ryder and Tom Westley both hit half-centuries as Essex were bowled out for 176, with Alfonso Thomas picking up four wickets for Somerset.
Chris Gayle led the reply for Somerset, hitting 92 off 59 deliveries, before Lewis Gregory and Max Waller scrambled for the winning run in the final over.
Results in full:
Kent Spitfires (193-8) beat Surrey (170-8) by 23 runs
Worcestershire Rapids (149-4)beat Leicestershire Foxes (147-6) by six wickets
Birmingham Bears (150-5) beat Northamptonshire (146-7) by five wickets
Hampshire (148-8) beat Glamorgan (127-8) by 21 runs
Derbyshire Falcons (128-5) beat Lancashire Lightning (127-9) by five wickets
Middlesex Panthers (221-2) beat Sussex Sharks (179-9) by 42 runs
Somerset (177-7) beat Essex Eagles (176) by three wickets
Durham Jets (182-4) beat Yorkshire Vikings (176-8) by six runs
