There were centuries today by two players who would love to be part of England's new-year tour to India.
Ben Foakes' unbeaten 112 for Surrey further underlined his batting credentials, while Hampshire's Liam Dawson staked a claim to be Test retiree Moeen Ali's replacement with 109 not out against Somerset.
It is possible for Durham to clinch promotion in this round of games and bowling out Sussex for 266 on day one at the Riverside has only increased the likelihood of that happening.
Join us tomorrow from 10:00 BST for coverage of day two in our seven games, and the start of Essex v Middlesex at Chelmsford.
Close of play scores
Division One
Hampshire 282-7 v Somerset
Northamptonshire 232 v Lancashire 54-2
Surrey 339-4 v Warwickshire
Division Two
Durham 6-0 v Sussex 266
Leicestershire 103-2 v Gloucestershire 159
Worcestershire 284 v Glamorgan 3-0
Yorkshire 297 v Derbyshire 47-1
Close of play at Leicester
Leicestershire 103-2 v Gloucestershire 159
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Leicestershire are in the One-Day Cup final but are also focused on winning promotion from Championship Division Two despite starting this round of games in fifth place.
They are well on top following the opening day against Gloucestershire, having bowled out the visitors in just 69.5 overs.
Tom Scriven was the pick with 4-30 from 16.5 overs and in-form opener Rishi Patel has pressed home their advantage with an unbeaten 60, including nine fours.
They have a strong batting line-up for this game, with recent signings Umar Amin and Ben Cox, and cup hero Wiaan Mulder to come.
Close of play at Scarborough
Yorkshire 297 v Derbyshire 47-1
Mitch Wagstaff plays out a maiden from George Hill to end the opening day at Scarborough as Derbyshire reach stumps with only one wicket down.
Having put Yorkshire in, the visitors will be content to have restricted them to a single batting point, with all-rounder Anuj Dal taking 5-72.
James Wharton made 58 for Yorkshire but no-one could go beyond that despite several team-mates making good starts.
Wagstaff will resume 32 not out, with Brooke Guest - who earlier took six catches behind the stumps - unbeaten on 13.
Close of play at Wantage Road
Northants 232 v Lancashire 53-2
Despite that drop, Will WIlliams has done a fine job of protecting Josh Bohannon (20*) across the last couple of overs.
Jack White missed his stumps by an inch as Williams shouldered arms and then saw the edge put down by Emilio Gay in the final over so Northants have to settle for two wickets in this final mini-session.
Earlier Sam Whiteman's 79 helped Northants to a modest total of 232. The deficit is 178.
In total 286 runs. 12 wickets. One captivating day of Championship cricket.
Close of play at the Ageas Bowl
Hampshire 282-7 v Somerset
Liam Dawson has led the way for Hampshire with an unbeaten century after the home side struggled earlier in the day against Somerset's bowling attack.
Dawson reached stumps on 109 not out, his second hundred of the season, to rescue Hampshire from 95-4.
Nick Gubbins battled manfully for his 49 before falling to Shoaib Bashir, but James Fuller and Keith Barker - who remains at the crease on 20 - both took advantage to help Dawson lead the recovery as the visiting bowlers tired in hot conditions.
Dropped catch
Northants 232 v Lancashire 54-2
Emilio Gay has put down Will Williams at second slip in the final over off Jack White.
The edge came fast and high above his shoulder, but he could only parry and then couldn't corral it on his way down either.
Three down would have been a fantastic result for Northants tonight.
for Rishi Patel
Leics 95-2 v Gloucs 159
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What a season this has been for Leicestershire opener Rishi Patel.
He reaches 50 for the seventh time by clipping a full toss from Luke Charlesworth away for an easy boundary - this one taking him just 54 balls.
Four of the previous six were converted into hundreds and two balls later he glances fine for another boundary.
Close of play at New Road
Worcs 284 v Glamorgan 3-0
Eddie Byrom and nightwatchman James Harris safely negotiate an over apiece from Joe Leach and Dillon Pennington to bring down the curtain on a fairly even day between these promotion contenders.
It looked for much of the day as through Glamorgan would take control, reducing the home side to 33-3 and then 110-6.
But Brett D'Oliveira, who finished 74 not out, shared a century partnership with Logan van Beek (53) and Ben Allison - also making his County Championship debut for Worcestershire - contributed 37 to hoist the Pears to a competitive total.
WICKET: Jennings lbw b White 19
Northants 232 v Lancashire 52-2
Keaton Jennings doesn't like this decision. He stays put in his crease, for once, and tries to glance the ball off his hips as it's angled across him by Jack White.
He can't connect and it hits him high on the pads. It might even be too high. And it might have been heading down leg.
Either way White is delighted as the finger is raised. Northants have a big scalp in the gloaming.
Will WIlliams is a night... something. Watcher? Hawk? Time will tell. 15 balls to come tonight.
for Liam Dawson
Hampshire 263-7 v Somerset
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Great knock by Liam Dawson, who crunches Tom Abell through the off side for three to take him to his second hundred of the season.
It's taken Dawson 183 balls to reach the landmark - his 13th first-class ton overall - and he's done an impressive job in holding this Hampshire innings together.
Just 3.5 overs left until stumps.
Post update
Northants 232 v Lancashire 52-1
Keaton Jennings has 19 from 51 balls and Josh Bohannon has 19 from 22 balls.
That tells a story.
Jennings has survived a couple of appeals and got away with an inside edge, though he keeps trying to be positive and charging down the track at regular intervals - he just can't get bat on ball when he does. He has steered his side past 50 though, just 180 behind.
Four overs to come tonight.
Close of play at the Riverside
Durham 6-0 v Sussex 266
The champions-to-be look liked champions this afternoon.
Matt Parkinson took 4-58 and Ben Raine passed 50 wickets for the season as Durham recovered to whip out visiting Sussex in the final session.
Tom Haines, Tom Clark and Tom Alsop all posted half-centuries but in truth the visitors contributed to their own demise after being 110-0 and lost their final five wickets for the addition of just 19 runs.
Durham will resume in the morning just 260 in arrears.
Division Two update
Gloucestershire have collected a second wicket at Grace Road, with Lewis Hill caught in the gully off Dom Goodman for 21.
Leicestershire are 71-2, 88 behind, with nine overs remaining in the day's play.
Mitch Wagstaff has made a positive start to his innings for Derbyshire, with 20 not out made up of five fours, and they are 32-1 in the 10th over after bowling out Yorkshire for 297.
Close of play at The Oval
Surrey 339-4 v Warwickshire
If Ben Foakes felt any guilt about the run out of Dom Sibley for 65, he has certainly done his bit to atone for it.
The England wicketkeeper ends day one on 112, having shared an unbroken partnership of 152 with Cameron Steel (69 not out).
Surrey were asked to bat first by Warwickshire, but the Bears attack were unable to justify Will Rhodes' decision, with Jamie Smith (60) also contributing a half-century.
The Division One leaders have packed five pace bowlers into their XI for this game. They will be looking for a 500+ total and hoping they can then get more out of the pitch when it is time for Warwickshire's reply.
Post update
Durham 0-0 v Sussex 266
After a maiden opening over from the Indian paceman, Ari Karvelas, the Greek international, takes the second over, bowling to Scotland's Mchael Jones.
What an exotic game the County Championship is.
Just one over to come after this one.
Worcestershire bowled out
Worcs 284 v Glamorgan
Zain ul Hassan collects his second wicket, with Kiran Carlson taking the catch to dismiss Dillon Pennington and the Pears are all out.
Huge credit to skipper Brett D'Oliveira, who batted three and a half hours for his unbeaten 74 and shared key partnerships with Logan van Beek and Ben Allison.
Glamorgan's openers will have two overs to survive before stumps...
up for Hampshire
Hampshire 245-7 v Somerset
It's been slow progress for Hampshire, but they've collected their first bonus point of the game, largely thanks to Liam Dawson.
The all-rounder, who's just belted Neil Wagner to the cover boundary, is six short of his hundred, with Keith Barker alongside him on six.
Post update
Northants 232 v Lancashire 43-1
Tom Taylor is brought into the attack and immediately gets some movement through the air from the Dukes ball while another delivery keeps very low indeed.
Keaton Jennings is looking at the track like it's a shark-infested paddling pool he's been asked to walk across.
Seven overs to come. Might be interesting ones too.
Post update
Durham 0-0 v Sussex 266
After collecting maximum bowling points, Durham will now set about seeing out the final three overs of the day.
Alex Lees and Michael Jones stride out in the lengthening shadows.
Jaydev Unadkat takes the new ball, on debut. No Ollie Robinson in the Sussex attack, remember.
Live Reporting
Alex Hoad, Ben Kosky and Paul Grunill
All times stated are UK
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Latest PostSigning off
There were centuries today by two players who would love to be part of England's new-year tour to India.
Ben Foakes' unbeaten 112 for Surrey further underlined his batting credentials, while Hampshire's Liam Dawson staked a claim to be Test retiree Moeen Ali's replacement with 109 not out against Somerset.
It is possible for Durham to clinch promotion in this round of games and bowling out Sussex for 266 on day one at the Riverside has only increased the likelihood of that happening.
Join us tomorrow from 10:00 BST for coverage of day two in our seven games, and the start of Essex v Middlesex at Chelmsford.
Close of play scores
Division One
Hampshire 282-7 v Somerset
Northamptonshire 232 v Lancashire 54-2
Surrey 339-4 v Warwickshire
Division Two
Durham 6-0 v Sussex 266
Leicestershire 103-2 v Gloucestershire 159
Worcestershire 284 v Glamorgan 3-0
Yorkshire 297 v Derbyshire 47-1
Close of play at Leicester
Leicestershire 103-2 v Gloucestershire 159
Leicestershire are in the One-Day Cup final but are also focused on winning promotion from Championship Division Two despite starting this round of games in fifth place.
They are well on top following the opening day against Gloucestershire, having bowled out the visitors in just 69.5 overs.
Tom Scriven was the pick with 4-30 from 16.5 overs and in-form opener Rishi Patel has pressed home their advantage with an unbeaten 60, including nine fours.
They have a strong batting line-up for this game, with recent signings Umar Amin and Ben Cox, and cup hero Wiaan Mulder to come.
Close of play at Scarborough
Yorkshire 297 v Derbyshire 47-1
Mitch Wagstaff plays out a maiden from George Hill to end the opening day at Scarborough as Derbyshire reach stumps with only one wicket down.
Having put Yorkshire in, the visitors will be content to have restricted them to a single batting point, with all-rounder Anuj Dal taking 5-72.
James Wharton made 58 for Yorkshire but no-one could go beyond that despite several team-mates making good starts.
Wagstaff will resume 32 not out, with Brooke Guest - who earlier took six catches behind the stumps - unbeaten on 13.
Close of play at Wantage Road
Northants 232 v Lancashire 53-2
Despite that drop, Will WIlliams has done a fine job of protecting Josh Bohannon (20*) across the last couple of overs.
Jack White missed his stumps by an inch as Williams shouldered arms and then saw the edge put down by Emilio Gay in the final over so Northants have to settle for two wickets in this final mini-session.
Earlier Sam Whiteman's 79 helped Northants to a modest total of 232. The deficit is 178.
In total 286 runs. 12 wickets. One captivating day of Championship cricket.
Close of play at the Ageas Bowl
Hampshire 282-7 v Somerset
Liam Dawson has led the way for Hampshire with an unbeaten century after the home side struggled earlier in the day against Somerset's bowling attack.
Dawson reached stumps on 109 not out, his second hundred of the season, to rescue Hampshire from 95-4.
Nick Gubbins battled manfully for his 49 before falling to Shoaib Bashir, but James Fuller and Keith Barker - who remains at the crease on 20 - both took advantage to help Dawson lead the recovery as the visiting bowlers tired in hot conditions.
Dropped catch
Northants 232 v Lancashire 54-2
Emilio Gay has put down Will Williams at second slip in the final over off Jack White.
The edge came fast and high above his shoulder, but he could only parry and then couldn't corral it on his way down either.
Three down would have been a fantastic result for Northants tonight.
for Rishi Patel
Leics 95-2 v Gloucs 159
What a season this has been for Leicestershire opener Rishi Patel.
He reaches 50 for the seventh time by clipping a full toss from Luke Charlesworth away for an easy boundary - this one taking him just 54 balls.
Four of the previous six were converted into hundreds and two balls later he glances fine for another boundary.
Close of play at New Road
Worcs 284 v Glamorgan 3-0
Eddie Byrom and nightwatchman James Harris safely negotiate an over apiece from Joe Leach and Dillon Pennington to bring down the curtain on a fairly even day between these promotion contenders.
It looked for much of the day as through Glamorgan would take control, reducing the home side to 33-3 and then 110-6.
But Brett D'Oliveira, who finished 74 not out, shared a century partnership with Logan van Beek (53) and Ben Allison - also making his County Championship debut for Worcestershire - contributed 37 to hoist the Pears to a competitive total.
WICKET: Jennings lbw b White 19
Northants 232 v Lancashire 52-2
Keaton Jennings doesn't like this decision. He stays put in his crease, for once, and tries to glance the ball off his hips as it's angled across him by Jack White.
He can't connect and it hits him high on the pads. It might even be too high. And it might have been heading down leg.
Either way White is delighted as the finger is raised. Northants have a big scalp in the gloaming.
Will WIlliams is a night... something. Watcher? Hawk? Time will tell. 15 balls to come tonight.
for Liam Dawson
Hampshire 263-7 v Somerset
Great knock by Liam Dawson, who crunches Tom Abell through the off side for three to take him to his second hundred of the season.
It's taken Dawson 183 balls to reach the landmark - his 13th first-class ton overall - and he's done an impressive job in holding this Hampshire innings together.
Just 3.5 overs left until stumps.
Post update
Northants 232 v Lancashire 52-1
Keaton Jennings has 19 from 51 balls and Josh Bohannon has 19 from 22 balls.
That tells a story.
Jennings has survived a couple of appeals and got away with an inside edge, though he keeps trying to be positive and charging down the track at regular intervals - he just can't get bat on ball when he does. He has steered his side past 50 though, just 180 behind.
Four overs to come tonight.
Close of play at the Riverside
Durham 6-0 v Sussex 266
The champions-to-be look liked champions this afternoon.
Matt Parkinson took 4-58 and Ben Raine passed 50 wickets for the season as Durham recovered to whip out visiting Sussex in the final session.
Tom Haines, Tom Clark and Tom Alsop all posted half-centuries but in truth the visitors contributed to their own demise after being 110-0 and lost their final five wickets for the addition of just 19 runs.
Durham will resume in the morning just 260 in arrears.
Division Two update
Gloucestershire have collected a second wicket at Grace Road, with Lewis Hill caught in the gully off Dom Goodman for 21.
Leicestershire are 71-2, 88 behind, with nine overs remaining in the day's play.
Mitch Wagstaff has made a positive start to his innings for Derbyshire, with 20 not out made up of five fours, and they are 32-1 in the 10th over after bowling out Yorkshire for 297.
Close of play at The Oval
Surrey 339-4 v Warwickshire
If Ben Foakes felt any guilt about the run out of Dom Sibley for 65, he has certainly done his bit to atone for it.
The England wicketkeeper ends day one on 112, having shared an unbroken partnership of 152 with Cameron Steel (69 not out).
Surrey were asked to bat first by Warwickshire, but the Bears attack were unable to justify Will Rhodes' decision, with Jamie Smith (60) also contributing a half-century.
The Division One leaders have packed five pace bowlers into their XI for this game. They will be looking for a 500+ total and hoping they can then get more out of the pitch when it is time for Warwickshire's reply.
Post update
Durham 0-0 v Sussex 266
After a maiden opening over from the Indian paceman, Ari Karvelas, the Greek international, takes the second over, bowling to Scotland's Mchael Jones.
What an exotic game the County Championship is.
Just one over to come after this one.
Worcestershire bowled out
Worcs 284 v Glamorgan
Zain ul Hassan collects his second wicket, with Kiran Carlson taking the catch to dismiss Dillon Pennington and the Pears are all out.
Huge credit to skipper Brett D'Oliveira, who batted three and a half hours for his unbeaten 74 and shared key partnerships with Logan van Beek and Ben Allison.
Glamorgan's openers will have two overs to survive before stumps...
up for Hampshire
Hampshire 245-7 v Somerset
It's been slow progress for Hampshire, but they've collected their first bonus point of the game, largely thanks to Liam Dawson.
The all-rounder, who's just belted Neil Wagner to the cover boundary, is six short of his hundred, with Keith Barker alongside him on six.
Post update
Northants 232 v Lancashire 43-1
Tom Taylor is brought into the attack and immediately gets some movement through the air from the Dukes ball while another delivery keeps very low indeed.
Keaton Jennings is looking at the track like it's a shark-infested paddling pool he's been asked to walk across.
Seven overs to come. Might be interesting ones too.
Post update
Durham 0-0 v Sussex 266
After collecting maximum bowling points, Durham will now set about seeing out the final three overs of the day.
Alex Lees and Michael Jones stride out in the lengthening shadows.
Jaydev Unadkat takes the new ball, on debut. No Ollie Robinson in the Sussex attack, remember.