In Division One, victories earlier for Surrey, Kent, Lancashire and Hampshire, while the game at Taunton was abandoned as a draw.
The Division Two matches at Lord's and Derby could not match that excitement as they ended in draws, but Sam Northeast was the individual star as he moved to the brink of Glamorgan history with his 308 not out. You can find a report of whether he breaks that on the website tomorrow.
Our live coverage returns on Monday with a full complement of fixtures in Division One, the pick of which looks like being Yorkshire v Hampshire as James Vince takes his title chasers to Scarborough.
Thanks for your company this week, and we hope you can join us then.
Close of play at Leicester
Leicestershire 584 v Glamorgan 563-5
The day ends fittingly with a four from Sam Northeast.
He finishes 308 not out, one short of equalling Steve James' Glamorgan record of 309.
As for the game, the Welsh side trail by just 21 runs.
for Sam Northeast
Leicestershire 584 v Glamorgan 558-5
Absolutely outstanding batting from Sam Northeast as he rocks back and crashes another one to the boundary.
His first triple century in his 192nd first-class match. Remember, his previous highest score was 191.
Northeast has gone from 200 to 300 in only 74 deliveries.
And he is now the second highest scorer in an innings for Glamorgan.
200 partnership
Leicestershire 584 v Glamorgan 535-5
Sam Northeast gets another couple and the sixth-wicket partnership is now worth 200.
He and Chris Cooke have accumulated those runs in 35.4 overs, at 5.6 runs per over - an excellent rate.
The deficit is down to under 50 and if any team could force in this game - however unlikely - it's Glamorgan.
From 9-2...
Leicestershire 584 v Glamorgan 520-5
To think, Sam Northeast came to the wicket yesterday with Glamorgan 9-2, a deficit of 575.
That margin is now down to 64 and Northeast is on 280 not out, and he has just clocked up his 1,000th run of the Championship season.
Knocks of this size don't do any harm for the average, do they?
for Chris Cooke
Leicestershire 584 v Glamorgan 507-5
Chris Cooke was dropped twice early on but the Glamorgan wicketkeeper has played a valuable foil to Sam Northeast.
Their partnership is worth 173, and Cooke's contribution is now exactly 50 off 101 balls.
James' club record in Northeast's sights
Leicestershire 584 v Glamorgan 498-5
Getty ImagesCopyright: Getty Images
With this impressive acceleration from Sam Northeast since getting to 200, some big records are looming on the horizion.
Northeast is now on 265 not out. The highest individual score for Glamorgan is 309 scored by Steve James against Sussex at Colwyn Bay in 2000.
Of course James played for England and these days is a fine sportswriter.
for Sam Northeast
Leicestershire 584 v Glamorgan 480-5
Sam Northeast must be enjoying himself at the crease.
He has gone from 200 to 250 in just 33 deliveries with a flurry of boundaries and he brings up his 250 with a 31st four of the innings.
Post update
Leicestershire 584 v Glamorgan 460-5
Sam Northeast and Chris Cooke's stand is now worth 126 and Northeast is going from strength to strength as he reaches 236.
Post update
And then we were down to one.
Leicestershire against Glamorgan is still on day three and they play on...
BreakingMIDDLESEX DRAW WITH SUSSEX
Middlesex (485) drew with Sussex (523 & 181-9)
And that is that at Lord's.
Middlesex thought they were in with a chance of victory after reducing Sussex to 96-7 after lunch, but a maiden fifty from Ari Karvelas and fine support from Archie Lenham and Steven Finn took Sussex to safety.
Second-placed Middlesex are 23 points behind Division Two leaders Notts.
BreakingDERBYSHIRE DRAW WITH NOTTINGHAMSHIRE
Derbyshire (318 & 249-4) draw with Nottinghamshire (618-8 dec)
Nottinghamshire captain Steven Mullaney shakes hands with the Derbyshire batters and that is that at Derby.
The pitch wins (with a bit of help from the rain this morning), but the match will be remembered for that club record second-wicket partnership for Notts of 402 between Ben Duckett and Haseeb Hameed.
Notts remain well clear of the rest in Division Two, Derbyshire stay in the pack chasing second.
Welsh side avoid the follow-on
Leicestershire 584 v Glamorgan 435-5
Sam Northeast guides one down to third and that is enough to ensure the follow-on target is met.
The 32-year-old is still going strong on 220 not out.
WICKET Karvelas c Hollman b Robson 57
Middlesex v Sussex 178-9 (lead by 216)
A really fine innings by Ari Karvelas on debut comes to an end as Sam Robson picks up just his ninth first-class wicket.
That tells you where the game is going...
Post update
Middlesex v Sussex 177-8 (lead by 216)
The game is going through the motions at Lord's now. Ari Karvelas and Steven Finn, who's batted for 57 deliveries, have salvaged a draw for Sussex.
for Sam Northeast
Leicestershire 584 v Glamorgan 411-5
A lovely drive down the ground off Callum Parkinson gets Sam Northeast four and it brings up his 200.
It is a first double ton for the ex-Kent and Hampshire batter, going past his previous best of 191.
He has also helped Glamorgan to a maximum five batting points.
Getty ImagesCopyright: Getty Images
for Karvelas
Middlesex v Sussex 172-8 (lead by 210)
That's an excellent maiden first-class half-century from Aristides Karvalas.
And it's an innings which has saved this game for Sussex.
The Greece all-rounder came to the crease when they were 96-7 and facing defeat. Now we're probably a few minutes away from handshakes.
Glamorgan duo moving closer to follow-on
Leicestershire 584 v Glamorgan 386-5
A 50 partnership between Sam Northeast and Chris Cooke for Glamorgan's sixth wicket.
This has blunted some of Leicestershire's momentum and they are now 49 away from avoiding the follow-on.
Post update
Middlesex v Sussex 161-8 (lead by 199)
We may well see handshakes at 17:00 BST if Middlesex don't take these last couple of wickets within an over or two.
29 overs remain, the Sussex lead is 199.
Bad day for the West Country
And it has been a bad day for the two sides at the bottom of Division One.
Gloucestershire's loss to Hampshire is their seventh in ten games and they are facing an immediate return to Division Two.
Somerset were in a strong position at Taunton to force a final day win over Yorkshire, but no play leaves them stuck in the bottom two. Although 2021 Champions Warwickshire will be looking over their shoulders after that collapse against Kent, their third loss in four games.
Live Reporting
Adam Lanigan and Gary Smee
All times stated are UK
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Getty ImagesCopyright: Getty Images 
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Latest PostSee you on Monday
The end of a fascinating day of cricket.
In Division One, victories earlier for Surrey, Kent, Lancashire and Hampshire, while the game at Taunton was abandoned as a draw.
The Division Two matches at Lord's and Derby could not match that excitement as they ended in draws, but Sam Northeast was the individual star as he moved to the brink of Glamorgan history with his 308 not out. You can find a report of whether he breaks that on the website tomorrow.
Our live coverage returns on Monday with a full complement of fixtures in Division One, the pick of which looks like being Yorkshire v Hampshire as James Vince takes his title chasers to Scarborough.
Thanks for your company this week, and we hope you can join us then.
Close of play at Leicester
Leicestershire 584 v Glamorgan 563-5
The day ends fittingly with a four from Sam Northeast.
He finishes 308 not out, one short of equalling Steve James' Glamorgan record of 309.
As for the game, the Welsh side trail by just 21 runs.
for Sam Northeast
Leicestershire 584 v Glamorgan 558-5
Absolutely outstanding batting from Sam Northeast as he rocks back and crashes another one to the boundary.
His first triple century in his 192nd first-class match. Remember, his previous highest score was 191.
Northeast has gone from 200 to 300 in only 74 deliveries.
And he is now the second highest scorer in an innings for Glamorgan.
200 partnership
Leicestershire 584 v Glamorgan 535-5
Sam Northeast gets another couple and the sixth-wicket partnership is now worth 200.
He and Chris Cooke have accumulated those runs in 35.4 overs, at 5.6 runs per over - an excellent rate.
The deficit is down to under 50 and if any team could force in this game - however unlikely - it's Glamorgan.
From 9-2...
Leicestershire 584 v Glamorgan 520-5
To think, Sam Northeast came to the wicket yesterday with Glamorgan 9-2, a deficit of 575.
That margin is now down to 64 and Northeast is on 280 not out, and he has just clocked up his 1,000th run of the Championship season.
Knocks of this size don't do any harm for the average, do they?
for Chris Cooke
Leicestershire 584 v Glamorgan 507-5
Chris Cooke was dropped twice early on but the Glamorgan wicketkeeper has played a valuable foil to Sam Northeast.
Their partnership is worth 173, and Cooke's contribution is now exactly 50 off 101 balls.
James' club record in Northeast's sights
Leicestershire 584 v Glamorgan 498-5
With this impressive acceleration from Sam Northeast since getting to 200, some big records are looming on the horizion.
Northeast is now on 265 not out. The highest individual score for Glamorgan is 309 scored by Steve James against Sussex at Colwyn Bay in 2000.
Of course James played for England and these days is a fine sportswriter.
for Sam Northeast
Leicestershire 584 v Glamorgan 480-5
Sam Northeast must be enjoying himself at the crease.
He has gone from 200 to 250 in just 33 deliveries with a flurry of boundaries and he brings up his 250 with a 31st four of the innings.
Post update
Leicestershire 584 v Glamorgan 460-5
Sam Northeast and Chris Cooke's stand is now worth 126 and Northeast is going from strength to strength as he reaches 236.
Post update
And then we were down to one.
Leicestershire against Glamorgan is still on day three and they play on...
BreakingMIDDLESEX DRAW WITH SUSSEX
Middlesex (485) drew with Sussex (523 & 181-9)
And that is that at Lord's.
Middlesex thought they were in with a chance of victory after reducing Sussex to 96-7 after lunch, but a maiden fifty from Ari Karvelas and fine support from Archie Lenham and Steven Finn took Sussex to safety.
Second-placed Middlesex are 23 points behind Division Two leaders Notts.
BreakingDERBYSHIRE DRAW WITH NOTTINGHAMSHIRE
Derbyshire (318 & 249-4) draw with Nottinghamshire (618-8 dec)
Nottinghamshire captain Steven Mullaney shakes hands with the Derbyshire batters and that is that at Derby.
The pitch wins (with a bit of help from the rain this morning), but the match will be remembered for that club record second-wicket partnership for Notts of 402 between Ben Duckett and Haseeb Hameed.
Notts remain well clear of the rest in Division Two, Derbyshire stay in the pack chasing second.
Welsh side avoid the follow-on
Leicestershire 584 v Glamorgan 435-5
Sam Northeast guides one down to third and that is enough to ensure the follow-on target is met.
The 32-year-old is still going strong on 220 not out.
WICKET Karvelas c Hollman b Robson 57
Middlesex v Sussex 178-9 (lead by 216)
A really fine innings by Ari Karvelas on debut comes to an end as Sam Robson picks up just his ninth first-class wicket.
That tells you where the game is going...
Post update
Middlesex v Sussex 177-8 (lead by 216)
The game is going through the motions at Lord's now. Ari Karvelas and Steven Finn, who's batted for 57 deliveries, have salvaged a draw for Sussex.
for Sam Northeast
Leicestershire 584 v Glamorgan 411-5
A lovely drive down the ground off Callum Parkinson gets Sam Northeast four and it brings up his 200.
It is a first double ton for the ex-Kent and Hampshire batter, going past his previous best of 191.
He has also helped Glamorgan to a maximum five batting points.
for Karvelas
Middlesex v Sussex 172-8 (lead by 210)
That's an excellent maiden first-class half-century from Aristides Karvalas.
And it's an innings which has saved this game for Sussex.
The Greece all-rounder came to the crease when they were 96-7 and facing defeat. Now we're probably a few minutes away from handshakes.
Glamorgan duo moving closer to follow-on
Leicestershire 584 v Glamorgan 386-5
A 50 partnership between Sam Northeast and Chris Cooke for Glamorgan's sixth wicket.
This has blunted some of Leicestershire's momentum and they are now 49 away from avoiding the follow-on.
Post update
Middlesex v Sussex 161-8 (lead by 199)
We may well see handshakes at 17:00 BST if Middlesex don't take these last couple of wickets within an over or two.
29 overs remain, the Sussex lead is 199.
Bad day for the West Country
And it has been a bad day for the two sides at the bottom of Division One.
Gloucestershire's loss to Hampshire is their seventh in ten games and they are facing an immediate return to Division Two.
Somerset were in a strong position at Taunton to force a final day win over Yorkshire, but no play leaves them stuck in the bottom two. Although 2021 Champions Warwickshire will be looking over their shoulders after that collapse against Kent, their third loss in four games.
8 Warwickshire - 99pts
9 Somerset - 87
10 Gloucestershire - 57