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Eight games start on Sunday - four each in Divisions One and Two
Division One leaders Surrey playing Kent at Canterbury
Durham, who are top of Division Two, hosting Glamorgan
Kent 211-8 v Surrey
Jordan Cox has spent approaching three-and-a-half hours in the middle and is 12 runs away from his first century of the season.
Wes Agar faces the first over of the evening session from Jordan Clark.
Essex 243-3 v Somerset
Ahhhhhhh that looks painful for Craig Overton. The Somerset pace bowler turns his ankle as he lands for his delivery stride and cries out in pain as he falls to the deck.
He's back on his feet after a minute or so, but he's now limping off with his left boot in his hand.
I've done that many a time and, let me tell you, they hurt. They really hurt. Get the ice pack on it quickly.
Essex 243-3 v Somerset
Credit to Somerset's bowling attack, they've kept plugging away throughout the day and have probably bowled better than an Essex total of 240-3 would suggest.
Craig Overton's lbw appeal against Matt Critchley is turned away.
Alastair Cook remains on 94 not out and has not added to his score since tea.
Durham v Glamorgan 251-4
Glamorgan batter Kiran Carlson scored 192 in his last County Championship innings... and the 25-year-old now has another century to his name.
It's his fourth hundred of a superb campaign and second against Durham after his 119 in April.
Sam Northeast went for 60, but the visitors are in control against the Division Two leaders.
Notts v Warwickshire 227-3
Warwickshire are in control at tea on day one at Trent Bridge.
Will Rhodes and Alex Davies, who fell seven runs short of a hundred, were the batters to be dismissed during the afternoon session.
But the Bears have accumulated steadily and the unbroken fourth-wicket stand between Sam Hain (45 not out) and Dan Mousley (30 not out) is worth 58.
Lancashire v Hampshire 142
Mason Crane miscues one to mid-off off Jack Blatherwick and is caught by Tom Bailey for 18.
That's all she wrote. Keith Barker's eye-catching 44 hauled the visitors from 76-7 into three figures but Lancashire were just too good with the ball.
Will Williams took 3-14 off 15 overs, Tom Bailey 3-29 with Blatherwick finishing with 2-25 and spinner Tom Hartley claiming 2-10 off five.
Can Hampshire's three spinners find similar fortune? We'll find out after tea.
Kent 211-8 v Surrey
The 121-run stand for the sixth wicket between Joey Evison (58) and Jordan Cox, who is unbeaten on 88 at tea, has kept Kent alive on the opening day.
Surrey have plugged away and found some joy with the spinners claiming three wickets towards the end of the session. They'll want to whip the last two out asap after taking tea and let Rory Burns and Dom Sibley get cracking on the chase, which looks unlikely to be intimidating.
Lancashire v Hampshire 142-9
Kyle Abbott goes big off the spinner, but not big enough, as Will Williams takes a smart catch near the long-off rope to give Tom Hartley a second scalp.
Mason Crane is joined by Mohammad Abbas. Who is thumped on the pads with the first ball. Nothing doing.
Notts v Warwickshire 204-3
We said earlier on that Sam Hain had started a little slowly but he picks up the pace with three fours in a Matthew Montgomery over and is now 36 not out at Trent Bridge.
The third one, down towards long on, results in a brief search for the ball.
Five overs left until tea.
Sussex 205-7 v Worcestershire
Those rain showers are really pepping up in the south of England now and one has arrived at Hove.
The players head off and that'll be tea. Hopefully it'll rattle through quite quickly.
A couple of overs before the rain interruption, Worcestershire seamer Matt Waite picked up the important wicket of Oli Carter for 76.
Kent 200-8 v Surrey
Wes Agar clips the final ball of Gus Atkinson's over into the leg side for a single to bring up the Kent 200. At 41-5 that milestone seemed a very long way away.
Three overs til tea.
Kent 199-8 v Surey
Matt Quinn takes a bouncer from Gus Atkinson on the shoulder and two balls later gets yorked all ends up by the Surrey paceman.
Leg stump goes flying. Textbook stuff.
Wes Agar strides out to support Jordan Cox.
Essex 235-3 v Somerset
Another solid session for the home side under sunny skies at Chelmsford.
Somerset managed to get rid of Tom Westley just after lunch, but Alastair Cook remains unbeaten on 94 and Matt Critchley appears in an aggressive mood - he's 35 not out as the players head off for tea.
Lancashire v Hampshire 134-8
Keith Barker plays a sublime inside-out stroke to crack spinner Tom Hartley into the sight-screen for a straight six.
Hartley replies with the very next ball, lofting one outside off which Barker tries to thrash through mid-wicket but misses completely, allowing the ball to whack his off stump.
Six fours and a six in a 71-ball stay which has changed the complexion of this innings, it's fair to say. The 58-run partnership is broken. Mason Crane has 12 and is joined by Kyle Abbott.
Essex 231-3 v Somerset
No sign of playing for tea at Chelmsford from Matt Critchley.
He follows a gorgeous straight drive off Matt Henry with a powerful pull shot for another boundary.
He's on 31 off 25 balls with an over to go until the interval.
Kent 194-7 v Surrey
Jordan Cox pulls back-to-back fours through the leg side off Dan Moriarty and carves the final ball for a single to move onto 82 from 129 balls.
He averaged 20-odd this morning. Kent will hope this is a season-changing knock for him.
Lancashire v Hampshire 127-7
Barker & Crane Salvage Operatives could easily be a real company.
Keith Barker and Mason Crane have done a fine job for this eighth wicket at Southport, Crane produced a textbook drive past mid-off off Tom Hartley to move into double figures with a boundary. He even held the pose.
Barker has 37, Crane 12. They have added 51 from 102 balls. Useful.
Yorkshire have lost Adam Lyth for 48, but they're not into the lead against Derbyshire on 117-2. They're six in front and going along at more than five an over.
Glamorgan batter Sam Northeast has just joined his partner Kiran Carlson in going to a half-century at Durham. Glamorgan are 220-3 and the Division Two leaders are finding the going tough in the field.
Sussex are fighting back against Worcestershire. Wicketkeeper Oli Carter has an unbeaten 67 and has formed a good seventh-wicket stand with Nathan McAndrew (27 not out). They're 192-6.
It's still raining at Bristol with Gloucestershire on 45-0 against Leicestershire.
Notts v Warwickshire 177-3
Dan Mousley shows great confidence early in his innings, plonking Calvin Harrison back over his head and into the stand for six.
Kent 182-7 v Surrey
Jordan Cox times a sweep off Dan Moriarty to perfection to find the fine leg rope and move to 70.
Matt Quinn has eight from just two scoring shots, both back-foot punches past backward point to the ropes off Gus Atkinson. The first more convincing than the second, it must be said.