Sam Curran claims five as Surrey beat Somerset in top-of-the-table showdown
The visitors posted 195 for nine after losing the toss, Will Jacks smashing 60 off 43 balls and Chris Jordan a blistering 36 not out off just 12.
In reply, Somerset were restricted to 167 for nine, Tom Banton top scoring with 53 and Tom Abell making 39. Curran – who has been made an MBE in the King’s Birthday Honours list – finished with five for 26 as Surrey replaced their opponents in top spot.
Kent scored a record Lord’s T20 total as they beat Middlesex by 13 runs, despite a magnificent century from Max Holden.
Holden led his side’s assault on an improbable target of 229 with a career-best T20 knock of 121 not out from 59 balls to maintain the Seaxes’ hopes of finally breaking their duck in the tournament after eight defeats.
But Kent held on for their second successive win, having posted 228 for three thanks to Daniel Bell-Drummond, who struck 66 from 42 before Joe Denly savaged his former side’s ragged bowling attack with an unbeaten 73 from 37.
Essex made it four wins in a row by beating Glamorgan by four wickets, with academy graduate Feroze Khushi hitting a half-century.
Khushi crashed a 37-ball 61 as Essex comfortably chased down 175, despite losing three early wickets thanks to Jamie McIlroy’s four for 36.
Paul Walter contributed 43, before Daniel Sams (41) and Matt Critchley (16 not out) saw off most the remaining runs with 24 balls to spare.
Oli Carter and Brad Currie were the heroes as Sussex upset defending champions Hampshire at Hove to claim only their third win of the season.
Carter’s 64 helped Sussex to 183 for six, which did not look enough in quick-scoring conditions.
Hampshire subsequently slumped to 24 for four and although Liam Dawson made 59 off 34 balls, Sussex won by six runs, with debutant Currie having taken three wickets as well as producing a stunning catch.
Birmingham Bears moved to the top of the North Group after triumphing by 21 runs in their derby clash against Worcestershire at New Road.
Late hitting from Dan Mousley (49 not out) and Jacob Bethell (32 not out) helped set a challenging target as the visitors reached 196 for five.
Worcestershire captain Brett D’Oliveira then struck his first T20 half century of the season, top scoring with exactly 50, but his side struggled to break free from the Bears’ spinners and finished on 175 for six for a fourth successive loss.
Dawid Malan’s fifth half-century of this competition – a superb 79 off 45 balls – helped Yorkshire to a record-equalling sixth straight T20 win as they chased 196 to beat Leicestershire by eight wickets at Headingley.
Louis Kimber had bludgeoned a career-best unbeaten 59 off 38 to power the Foxes to 195 for five after a mixed start to the innings.
But he was on the losing side as Malan united with Adam Lyth (90 not out), the left-handers sharing a superb club-record opening stand of 158 in 14 overs.
Steven Croft smashed his maiden Blast century to power Lancashire to an imposing 204 for seven and set up a 35-run victory over Northamptonshire at Wantage Road.
Croft clubbed seven sixes and five fours in his 101 and shared a 146-run partnership in 12 overs with Daryl Mitchell (48).
Luke Wood then took three for 39 as the Steelbacks – for whom Tom Taylor and AJ Tye posted 40 and 35 respectively – fell to their sixth defeat of the campaign.
Durham and Derbyshire played out a thrilling tie at Seat Unique Riverside after Falcons batter Haider Ali hit the final ball of the innings for four to earn his team a share of the spoils.
Brydon Carse top scored for Durham with 58 as they posted 178 from their 20 overs. Luis Reece then hit 58 from 47 balls in Derbyshire’s reply, but the home side dragged it back to set up a tense finale as Wayne Parnell claimed three wickets.
Haider then held his nerve from the last ball, finding the boundary on the leg-side to claim a valuable point for his team.