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All 10 sides in Division One in action
Three games in Division Two, including opening day of leaders Notts v Sussex
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Gloucestershire 317 v Northants 99-1
New Zealand's Will Young and South Africa's Ryan Rickelton are together at the crease for Northants and they have added 53.
After a slow-ish start, their run-rate is starting to pick up as they put together a good partnership.
Essex 320-3 v Somerset
Nick Browne reaches his 150 for Essex with his 22nd boundary.
This is the 18th first-class century of his career - but the first time he has gone past 150 in five seasons.
Lancashire 145 v Kent 4-1
Lancashire are convinced they have Zak Crawley caught behind off Will Williams.
But the umpire gives nothing and Crawley survives, but still to get off the mark.
Not easy for batters here at all.
Essex 316-3 v Somerset
Nick Browne and Paul Walter take their fourth-wicket partnership to the 150-mark.
Browne's own 150 is set to follow. He is on 147 (unlikely to be his maximum break) and Walter is on 74.
Somerset have seemingly no answer.
Warwickshire 253, Surrey 20-1
Four overs gone for Surrey.
Five scoring shots.
All have gone to the boundary.
Image source, Rex FeaturesHashim Amla follows the example of Ryan Patel and Rory Burns before him as he too gets off the mark with a four.
But for a man who has hit 19,233 first-class runs, 10,019 in one-dayers and 4,563 in T20, for Liam Norwell to bowl Amla a full toss on leg stump was a bit of an open goal.
Lancashire 145 v Kent 0-1
Tom Bailey only needs two balls to strike!
Ben Compton is completely squared up by Bailey as he tries to steer to leg and is caught at point.
Seven wickets for 33 runs this morning at Old Trafford.
Ollie Robinson must have a point to prove as he has claimed all three Nottinghamshire wickets this morning. He has 3-26 for Sussex as the hosts are 47-3.
Ed Barnard is playing a useful hand for Worcestershire. He is 39 not out as they move to 184-8, a lead of more than on Derbyshire.
Michael Jones is within five of a century as Durham are 156-1 at home to Middlesex.
Lancashire 145 v Kent
Innings over at Old Trafford.
Will Williams' eyes light up when new bowler Nathan Gilchrist drops short and wide with his second ball.
It should be four but for a sensational grab by Daniel Bell-Drummond at gully as the ball sticks in his grasp.
Lanashire have lost 6-33 this morning in 55 minutes of action, with Matt Henry the star of the show.
What a difference to the Kent attack with him and India quick Navdeep Saini opening the bowling.
Warwickshire 253, Surrey 12-1
Remarkable start to the Surrey innings at The Oval.
Routine OHD maiden off the first, then Ryan Patel flays three of Liam Norwell's first four deliveries before looping a tame toe-ender off the fifth ball to a grateful Nathan McAndrew in the covers.
It's a first start of the season for fit-again Norwell, the Bears' top wicket taker when they won the Division One title last season, and it has taken him just five balls to add to his tally in the most unlikely of fashions.
Next man in for Surrey is prolific run maker Hashim Amla.
Yorkshire 159, Hampshire 3-1
Just 28 balls bowled this morning. Three wickets.
And now steady rain.
Not set fair in Scarborough then? It sounds like it might be a while before they get back on at North Marine Road.
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Lancashire 145-9 v Kent
Matt Henry has five!!
Perhaps the softest dismissal of his five this morning as Luke Wood chips one to Grant Stewart at mid-on.
5-15 this morning in the Kiwi's inspired spell.
Essex 301-3 v Somerset
Essex sneak in for a third batting bonus point - in the 107th over.
Slow going. There won't be any more before the all-important 110-over threshold.
Nick Browne is still going well on 141, with Paul Walter on 67 - and their fourth-wicket stand has reached 135 as England spinner Jack Leach comes on for his first trundle of the day.
Norwell b Lawes 7 (Warwickshire 253 v Surrey)
Warwickshire's innings comes to an end inside little more than half an hour at The Oval as Liam Norwell is last man out.
Tom Lawes weighs in with the final scalp, plucking out Norwell's middle stump, leaving OHD stranded, having added another 20 dot balls and 24 minutes' batting time to this season's impressive stats.
Now for Surrey openers Rory Burns and Ryan Patel to have their turn.
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Durham 141-1 v Middlesex
First wicket at Chester-le-Street and it's Alex Lees.
In his final red-ball match before the South Africa series, Lees has been bowled by Toby Roland-Jones, perhaps caught playing slightly across the line as the ball nips back and hits the off bail.
Coming off 134 balls, it is not quite the type of innings we have come to expect from England and their 'Baz-ball' Test players.
Wickets continue to tumble at New Road. After 15 yesterday, we have already had three this morning.
Worcestershire are now 154-8, leading Derbyshire by only 24, with seamer Ben Aitchison taking all three wickets to fall.
The Durham openers continue to keep Middlesex at bay. They are now 141-0 with Michael Jones on 87 and England man Alex Lees up to 46.
Yorkshire 159, Hampshire 3-1 (2,5 overs)
Ben Coad strikes. Ian Holland is gone.
First wicket for Yorkshire as Coad finds Holland's edge.
But new man Joe Weatherley does not even have time to make it to the middle before the already ugly looking clouds start to empty - and off they come again.
Lancashire 135-8 v Kent
The Matt Henry show continues!!
Outstanding stuff from the New Zealand quick as he gets one to pitch, swing away and knock over Tom Bailey's off-stump.
Four wickets in less than 30 minutes today and his figures are now 4-40.
Nottinghamshire 13-1 v Sussex
Sussex chose to bowl on day one at Trent Bridge and they have a wicket in the third over.
And it's gone to Ollie Robinson, in his first game of cricket since May because of a back problem, bowling Haseeb Hameed.
Remember this time last year, Robinson took 21 wickets in four Tests against India before going on to tour Australia until fitness and injury issues derailed him somewhat.
Yorkshire 159, Hampshire 3-0 (2 overs)
Hampshire openers Felix Organ and Ian Holland are off and running at Scarborough. But it is far from easy.
Fit-again Ben Coad bowls the first over on his first County Championship start in 10 months.
In cloudy conditions, Coad and Jordan Thompson must be relishing this.
Lancashire 133-7 v Kent
Third wicket in 20 minutes for Matt Henry!
Again he finds plenty of life in this Old Trafford pitch to take the edge of Steven Croft's bat.
This time, Jordan Cox hangs on despite a little juggle and Kent are now into the Lancashire tail.