Sam Curran takes 5-26 as Surrey beat Somerset to leapfrog them at top of South Group
Birmingham Bears go top of North Group with 21-run win at Worcestershire
Lyth (90 not out) & Malan (79) ease Yorkshire to eight-wicket win over Leicestershire
Croft hits 101 to set up Lancashire win by 35 runs at Northants
Champions Hampshire slip to narrow six-run loss at Sussex in last-over thriller
Essex recover from 1-2 to chase 176 to win and beat Glamorgan by four wickets
Haider hits last ball for four as Derbyshire earn tie at Durham
Kent beat Middlesex by 13 runs despite 121 not out by Holden
Kent 137-2 (13.3 overs) v Middx
A second Middlesex wicket at Lords's as dangerman Daniel Bell-Drummond is gone for 66, after clubbing eight fours and two sixes. A second wicket for Brett Cullen.
Durham 100-4 (11.5 overs) v Derbyshire
Brydon Carse moves to 31 and that brings up his side's 100.
Next ball and Ashton Turner has one of his stumps sent cartwheeling by Zaman Khan and his slingers.
Somerset v Surrey 96-1
Will Jacks picks up a couple of runs off Ben Green and reaches his second 50 of the competition from 37 balls faced.
Surrey will be hoping he can bat deep and help push this total well beyond 200, if possible.
Northants v Lancashire 82-3 (9.2 overs)
Steven Croft goes big as he starts a Freddie Heldreich over with a four and a six.
The stand between him and Daryl Mitchell is now worth 57 and is crucial to Lancashire's hopes of a good score.
Croft has 34 and Mitchell 25.
Birmingham Bears 196-5, Worcestershire 11-2 (2.1 overs)
Jack Haynes is strangled down the legside by Henry Brookes' first ball - and the Pears are suddenly in big trouble.
Another Bears old boy Adam Hose comes in to join Brett D'Oliveira.
Birmingham Bears 196-5, Worcestershire 10-1 (1.3 overs)
Ed Pollock fails to clear mid-off and he is gone against his old club.
Very tidy first over over from Glenn Maxwell. Just two runs off it.
Henry Brookes to bowl over number three.
Somerset v Surrey 80-1
We reach the half-way point of Surrey's innings at Taunton.
Sam Curran cracks the first ball of the 10th past cover for four, but there are only a couple of singles from the rest of Lewis Gregory's over.
Durham 88-3 (10.1 overs) v Derbyshire
The second half of Durham's innings starts with a wicket as the dangerous Ollie Robinson sees his off-stump is knocked out of the ground by George Scrimshaw.
Things evenly poised here.
Birmingham Bears 196-5, Worcestershire 9-0 (1 over)
Worcestershire openers Brett D'Oliveira and Ed Pollock make a sound start. Nine off the first over from Hasan Ali.
The Bears turns to Glenn Maxwell's spin for the second.
Essex v Glamorgan 11-0 (2 overs)
First boundary of the match at Chelmsford and it's a maximum for Glamorgan skipper Kiran Carlson off Daniel Sams.
More of those please Kiran!
Yorks v Leics 83-3
Two in two at Headingley as Ben Mike has Rishi Patel and Colin Ackermann caught from successive balls.
The first was a great piece of work by David Wiese who palmed it back at long-on to skipper Shan Masood who completed the catch.
Louis Kimber fends off the hat-trick with a single but the Foxes need to regroup for a couple of minutes now. We are in the ninth over.
Sussex 12-0 (1 over) v Hampshire
We are also under way now at Hove, where Tom Clark and Harrison Ward took 12 off Chris Wood's first over.
Northants v Lancashire 56-3 (7.2 overs)
Australia bowler Andrew Tye is thrown the ball and he is greeted with Daryl Mitchell hitting him for successive fours.
Northants would love to remove the dangerous New Zealand batter. He has 21 from nine balls.
Somerset v Surrey 71-1
Ben Green into the attack for Somerset and Laurie Evans swings his first ball to mid-wicket where it just lands just beyond the rope.
It's his final scoring shot, though as he is caught by Tom Abell from the next for 28. Evans will feel he's missed out there as that was a full toss by Green.
Good opening stand for Surrey. Sam Curran is in at three.
Kent 115-1 (11 overs) v Middx
Kent still going well at Lord's where the visitors have gone past 100 for only the loss of Tawanda Muyeye (33).
Daniel Bell-Drummond has gone to his 50 and Middlesex old boy Joe Denly is quickly into double figures.
Yorks v Leics 65-1
Jordan Thompson is among the leading wicket-takers in the competition and there's another for his collection as Nick Welch drills his third ball of the game to Dom Bess and deep extra cover.
The Foxes opener was looking dangerous so Yorkshire will be very happy with that.
Durham 60-2 (7.3 overs) v Derbyshire
Alex Lees, one of England's original Bazballers, is out and in unfortunate fashion.
He is run out as Brydon Carse drives one from Mattie McKiernan which the bowler diverts back onto the stumps, with Lees well out of his ground backing up.
In a different world, maybe he would have been part of the first Ashes Test at Edgbaston.
Northants v Lancashire 39-3 (6 overs)
The end of the powerplay at Wantage Road and no doubt who is in the ascendancy.
Daryl Mitchell has joined Steven Croft at the crease after Luke Wells became the third Lancashire batter to fall, giving Tom Taylor his first wicket.
The Red Rose have a lot of work to do to reach a competitive total here.
Birmingham Bears 196-5 (20 overs) v Worcestershire
Good late recovery from the men from Birmingham.
A 50 partnership in 18 balls between Dan Mousley (49) and Jacob Bethell (32).
The last four overs went for 56. Unexpectedly expensive that for Worcestershire.
Big test now for Ed Pollock against his old club.
Durham 52-1 (6.4 overs) v Derbyshire
Brydon Carse gets a rare three in T20 cricket off the left-arm spin of Mark Watt to bring up his side's 50 in the seventh over.