Alastair Cook showed his desire for runs remains as unquenchable as ever as he hit an immaculate century for Essex against Surrey at The Oval on a day otherwise dominated by bowlers.
The former England captain hit 140 not out as Essex reached 299-3, backed by a half-century from the latest Essex player to reach the England ranks, Dan Lawrence.
It was his fifth first-class century at The Oval, where he has hit more hundreds than at any other ground except Chelmsford and Lord's - not to mention his one and only England T20 ton.
"Alastair Cook's record obviously speaks for itself," Surrey assistant head coach Richard Johnson told BBC Radio London. "The hunger he still has for runs is incredible."
"It's been a bit of a slow season for me," said Cook, who had only reached three figures once this year. "It's an interesting pitch, with some good footmarks for Dan Moriarty outside my off stump. But not too much has actually happened off the wicket and it's a good one to bat on at the moment."
Surrey had Jonny Tattersall making his debut on an emergency wicketkeeping loan from Yorkshire - his second loan this summer, after also playing for Gloucestershire. He helped with two of the wickets to fall, catches off Jordan Clark and 39-year-old Rikki Clarke, making his final home appearance.
While 2019 county champions and 2020 Bob Willis Trophy winners Essex are intent on ending their reign in style by securing the third successive victory that would ensure top spot in Division Two, there is still much to play for elsewhere.
Chris Rushworth took his total of red-ball scalps for the season to 54 as he and Matt Potts helped Durham bowl out Northamptonshire for 183 at Wantage Road.
Scott Borthwick then hit an unbeaten half-century as Durham replied on 108-4 after David Bedingham had got the eight he needed to become the second batsman to reach 1,000 Championship runs this season - to match Sussex's Tom Haines' achievement last week.
Gloucestershire were without England's James Bracey against Glamorgan in Cardiff because of a concussion injury suffered in training, meaning a Championship debut for 21-year-old Ben Wells.
And although the visitors won the toss and opted to bowl first, it turned out to be dominated by the hosts.
David Lloyd, Hamish Rutherford and Eddie Byrom, on loan from Somerset, all made half-centuries before the hosts closed on 264-6.
Just like at Emerald Headingley, 18 wickets fell on the first day at Lord's.
After a poor season with the ball, Ed Barnard bounced back with 4-43 and skipper Joe Leach took 3-30 to become the first Worcestershire bowler to take 30 Championship wickets this season as the Pears hustled out Middlesex, who made their record score less than a week ago, for just 144.
Only Max Holden provided any real resistance with 52, his first half-century of the season.
But the hosts then hit back, as Tim Murtagh and Ethan Bamber reduced Worcestershire to 113-8 before bad light ended the suffering, although that included a long-awaited return to form for Gareth Roderick, whose 42 was his highest score for the county.
Sussex won the toss at Grace Road and went on to have a great day against Leicestershire, piling up 310-4.
After Ali Orr and Tom Haines added 106 for the first wicket, the Foxes then dropped Ben Brown just before lunch when he had made just three - and he made them pay, going on to hit 111 not out.
Kent rested Darren Stevens, Matt Milnes and Joe Denly ahead of T20 Finals Day this Saturday.
But it did not stop them having a good day, Jack Leaning, Daniel Bell-Drummond and England's Zak Crawley all hitting half-centuries as they were bowled out for 285, then removing Derbyshire opener Harry Came in the seven balls possible before the close.
Cardiff: Glamorgan 264-6 (Lloyd 73, Rutherford 62, Byrom 60*; T Price 3-44) v Gloucestershire
Wantage Road: Northants 183 (Procter 76; Potts 4-42, Rushworth 3-50), Durham 108-4 (Borthwick 54*)
The Oval: Essex 299-3 (A Cook 140*, Lawrence 78, Westley 47) v Surrey
Derby: Kent 285 (Leaning 82*, Bell-Drummond 69, Crawley 53; Aitchison 4-83), Derbyshire 1-1.
Leicester: Sussex 310-4 (Brown 111*, Haines 71, Orr 40, Carter 40) v Leicestershire.
Lord's: Middlesex 144 (Holden 52; Barnard 4-43, Leach 3-30), Worcestershire 113-8 (Roderick 42; Muragh 4-37, Bamber 3-29).