Division Two leaders Essex continued their dominance of Surrey on day two of their match at The Oval.
Alastair Cook top-scored with 165 in Essex’s 439 all out, and Surrey struggled to 107-7 in reply.
Only three home batsmen reached double figures, with captain Hashim Amla unbeaten on 58 at stumps.
Elsewhere in Division Two, Durham’s lower-order helped them to a first-innings lead of 217 at Northants, with the hosts reaching 10-0 at the close.
And it proved to be a good day for Gloucestershire as they reached 224-2 in reply to Glamorgan’s 309 all out.
In Division Three, centuries from Hassan Azad and Lewis Hill helped Leicestershire make a strong start to their reply to Sussex’s 359-9, in which Ben Brown scored an unbeaten 133.
In south London, Essex resumed on 299-3 and former England captain Cook added 25 runs to his overnight score before he was caught behind off the bowling of Dan Moriarty.
The visitors took lunch on 415-6, but lost their final four wickets for just 11 runs.
Surrey’s reply began badly with both openers out for ducks and Ollie Pope quickly following for five as they slid to 19-3.
Will Jacks battled almost an hour for his 11 and after Rikki Clarke hit a four and a six to get to 12, former South Africa great Amla had to be studious in defence as he sought to hold back the Essex tide.
Sam Cook, Jamie Porter and Simon Harmer all took two wickets apiece, and Surrey need another 183 on day three to avoid the follow-on.
Durham trailed Northamptonshire’s first innings score by 75 runs when they picked up on 108-4, but Scott Borthwick (73), Graham Clark (42) and Paul Coughlin (48) helped the visitors into the lead.
Matty Potts (81) and Liam Trevaskis (77 not out) then both collected half-centuries during a record-breaking ninth-wicket partnership in the evening session.
The 149 they put on was a Durham record against Northants and just one shy of the outright best against any county – as both batsmen registered their highest first-class scores.
The hosts navigated a nervy four-over spell under the floodlights before the close.
Gloucestershire picked up the final four Glamorgan wickets for 45 before lunch at Cardiff – with Eddie Byrom last to go for 78 – to bowl out out their opponents for 309.
The visitors then made a promising start to their reply before bad light brought an early close to play with them on 224-4.
Chris Dent went for 75, but Graeme van Buuren ended the day 65 not out alongside Ben Wells.
Worcestershire’s Josh Baker hit his maiden first-class half-century to help his side from 113-8 to 171 all out at Lord’s, as the 18-year-old finished 61 not out.
Table-toppers Middlesex trailed by 27 runs at they began their second innings but were in trouble at 39-4 after lunch following a burst from Charlie Morris (3-43).
John Simpson led the fight-back for the north Londoners, with Max Holden (46) and Martin Andersson (45) both contributing valuable runs.
Simpson was 59 not out at stumps, putting on an unbroken stand of 80 with Luke Hollman to steer Middlesex to 233-6 and an overall advantage of 206.
Kent enjoyed the better of day two at Derby, with Grant Stewart taking a wicket with the second ball of the day to remove Leus du Plooy for a duck and leave Derbyshire 1-2 in reply to Kent’s 285.
Captain Billy Godleman batted three hours for his 31 and Sam Conners (39) added some tail-end resistance as the hosts were dismissed for 156, with Stewart finishing with 5-23.
Zak Crawley (68) and Jordan Cox (58 not out) then stretched Kent’s lead to 276 as the visitors closed on 147-1.
Chris Wright (6-94) did the damage for Leicestershire, taking four of Sussex’s remaining wickets as the visitors lost their final five wickets for just 25 runs to finish on 359-9.
After the early loss of Sam Evans for a duck, Hassan Azad put on 103 for the second wicket with George Rhodes (37) and, along with Lewis Hill, had helped add 183 in an unbroken third-wicket stand before the close.
Azad reached stumps on 122 not out, with Hill unbeaten on 109, to put the Foxes 68 runs behind on 291-2.
Day Two scoreboards
Cardiff: Glamorgan 309 (Lloyd 73, Rutherford 62, Byrom 78; T Price 3-44) v Gloucestershire 224-4 (Dent 75, Van Buuren 65*; Salter 2-47).
Wantage Road: Northants 183 (Procter 76; Potts 4-42, Rushworth 3-50) & 10-0 v Durham 400 (Potts 81, Trevaskis 77*, Borthwick 73; Sanderson 4-41).
The Oval: Essex 439 (A Cook 165, Lawrence 78) v Surrey 107-7 (Amla 58*; Porter 2-17).
Derby: Kent 285 (Leaning 82*, Bell-Drummond 69, Crawley 53; Aitchison 4-83) & 147-1 (Crawley 68, Bell-Drummond 58*) v Derbyshire 156 (Conners 39; Stewart 5-23).
Leicester: Sussex 359-9 (Brown 133*, Haines 71; Wright 6-94) v Leicestershire 291-2 (Azad 122*, Hill 109*).
Lord’s: Middlesex 144 (Holden 52; Barnard 4-43) & 233-6 (Simpson 59*; Morris 3-43) v Worcestershire 171 (Baker 61*; Muragh 5-64).