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Kookaburra balls being used in this round of games plus first round in July
D1: Lancashire, put in by leaders Surrey, rally from 119-5 to be bowled out for 274
Teams who won the toss batting first in all the other games
D1: Essex duo Dan Lawrence and Tom Westley hit tons at home to Warwickshire
D1: Nick Gubbins & Liam Dawson going well for Hampshire against Middx
D1: Rob Keogh out for 97 for Northants against Kent in battle of bottom two
D1: Somerset bowled out for 163 at home to Nottinghamshire
D2: Alex Lees hits a ton as leaders Durham pile up a big score at Leicester
D2: Second-placed Sussex bowl out Glamorgan for 242
D2: Fin Bean makes a century for Yorkshire at home to Gloucestershire
D2: Pears opener Jake Libby still there but Pears four down at home to Derbyshire
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Worcestershire 234-9 Derbyshire
One wicket to go for Derbyshire to wrap-up the Worcestershire innings as Luis Reece gets his first wicket, bowling Josh Baker for 12.
Dillon Pennington and Navdeep Saini are the last two Pears standing.
Can they reach 250 and grab that first batting point?
Morley c Foakes b Clark 2 (74 overs) v Surrey
Jack Morley is last man out, Lancashire are bowled out for 274 - and Surrey now have to face 20 overs of Kookaburra before the close.
Awkward? Let‘s see!
Good effort from Lancashire old boy Jordan Clark against his former county. Like Sean Abbott, the Cumbrian ends up with four wickets, comfortably his best figures against Lancy.
Essex 326-5 (79.1 overs) v Warwickshire
Now fellow Bears spinner Dom Bess gets in on the act too.
Paul Walter departs cheaply, as he holes out to Dan Mousley.
Yorkshire 356-5 v Gloucestershire
Gloucestershire need a quick breakthrough and rapid change of fortunes with the new Kookaburra.
The first one went for 356 off its 80 overs, with George Hill (101) and Jonathan Tattersall (75 not out) racing from 300 to 350 in just 38 balls before Hill fell with the new ball beckoning.
Hampshire 232-4 v Middlesex
As if to drive home Kevin's point about piling on the pressure... Liam Dawson steps-up to hit his first six of the innings.
It feels like an age ago when Middlesex took their last wicket - that of Ben Brown, when Hampshire were looking vulnerable on 94-4.
It will seem even longer for the Middlesex bowlers I'd have thought.
Essex 317-4 (76.5 overs) v Warwickshire
A big moment for Warwickshire mystery spinner Jake Lintott as he takes his first County Championship wicket - at the age of 30.
Lintott has pretty much played white-ball crickety only for the Bears and for Southern Brave in The Hundred since packing in his job as a school teacher to try and make it in the professional ranks in 2020.
But in this, his second red-ball match, he can now claim Matt Critchley as his first scalp, well caught by Ed Barnard.
Hampshire 226-4 v Middlesex
Kevin Hand
BBC Radio London
With the new ball now available, Middlesex will hope for some early breakthroughs for the quicks to recover the momentum lost since Lunch.
Nick Gubbins, in his first match against the county he left in 2021, has anchored the innings while Liam Dawson has led the recovery with both eyeing centuries.
Gubbins was helped by a life on 61 but his top-edged sweep off Luke Hollman's leg spin was shelled by Ethan Bamber.
At four down with three figures yet to be reached, the toss looked about all Hampshire could happily walk away from day one with but Hampshire now have the chance to back the decision to bat first and pile the pressure on the visitors, who will have to bat last on a dry surface.
Somerset 163 v Nottinghamshire 79-2
An unfortunate way to go.
Matt Montgomery plays a Kasey Aldridge delivery on to the top of his pads and it bounces up and trickles back on to his off stump.
He had done the hard work and will be cursing his luck all the way to anyone who wishes to listen.
Notts trail by 84 runs as Joe Clarke comes to the crease fresh from a double century in his last Championship knock.
Lancashire 270-9 v Surrey
One attacking shot too many from Jack Blatherwick.
Jordan Clark picks up his third wicket against his old club.
Lancashire 268-8 v Surrey
Lancashire pick up their first batting point with the new Kookaburra as Jack Blatherwick takes on the role of senior batsman.
He then moves into his 30s with a six and a four off off Will Jacks.
Durham 280-4 v Leics
Martin Emmerson
BBC Radio Newcastle
There are 25 overs left today and it may take a bit of time to bowl them.
It's a very hot and windy day at Grace Road and the game seems to have slowed since tea.
Durham were 263-4 at tea having lost Scott Borthwick in the afternoon session for eight, David Bedingham for 16 and Alex Lees for 101.
It was his first century since making 105 against Sussex in April last year.
Since then Graham Clark (35) and Ollie Robinson (27) have added 59 runs.
Yorkshire 334-4 v Gloucestershire
A second century-maker for Yorkshire this afternoon.
George Hill follows his team-mate Fin Bean and brings up his fourth first-class ton with a single, turned to square leg.
The 22-year-old has cashed in on tiring bowlers and a lightning-quick outfield to reach the landmark off 177 balls, featuring 13 fours and two sixes.
At the other end Jack Tattersall has reached his half-century in 74 balls.
Not much fun to be had in the field I suspect.
Lancashire 248-8 v Surrey
Not a good moment for the first Kookaburra of the summer at The Oval.
Never mind the 80-over new ball mark, this first one has not made it past 67 overs - and has had to be changed.
Northamptonshire 237 v Kent 17-1
First wicket for Northants!
Ben Sanderson beats the defence of Ben Compton and the ball hits the top of off stump.
After making a fast start in the opening couple of overs Kent have pegged back the runs and now taken a wicket.
Somerset 163 v Nottinghamshire 55-1
It's not been easy but Ben Slater (36 not out) and Matt Montgomery (13 not out) are grinding it out nicely as they chip away at a small deficit.
Four byes off Craig Overton brings up the 50 after 23.1 overs and Notts trail by just 108.
Lancashire 238-8 (64.3 overs) v Surrey
Joy for Surrey in the first over after tea as Sean Abbott finds the edge from the third ball.
Phil Salt is gone for no further addition, to his teatime 56.
The tea break clearly did as much for him as it did Essex skipper Tom Westley. Salt did at least last two balls longer.
Yorkshire 314-4 v Gloucestershire
Yorkshire are beginning to motor.
George Wilson (94 not out) and Jonathan Tattersall (45 not out) have stepped on the gas after tea and taken Zafar Gohar's latest over for 19 runs, including a big six from Hill.
The pair have shared 71 for the fifth wicket and brought up a second batting point.
Northamptonshire 237 v Kent 16-0
Kent's reply has started well at Northampton.
Ben Compton and Tawanda Muyeye have both hit boundaries and the second over was an expensive one for Northants with 11 from it.
Hampshire 205-4 v Middlesex
Nick Gubbins and Liam Dawson have picked-up where they left off after tea.
Gubbins is now on 69 and Dawson 62, they've both hit eight fours and their partnership is worth 113.
Middlesex look like they don't have the combination to break them up at present.
Essex 247-3 (64.1 overs)
What do they put in the tea at Chelmsford!!!
Rejuvenated Warwickshire strike with the first ball after the restart as Ed Barnard removes Tom Westley.
Matt Critchley comes in to join Westley's fellow Essex centurion Dan Lawrence.