Adam Rossington's century and an unbeaten 83 from Matt Critchley rescued Essex after a false start to their crunch County Championship clash against Hampshire.
Durham have secured promotion back to Division One of the County Championship.
Zak Crawley's 158 inspired Kent to 387-4 on the opening day of their LV= County Championship Division One game with Nottinghamshire.
Surrey thumped Warwickshire by an innings and 97 runs to move closer to successive LV= Insurance County Championship titles.
Lancashire seamers Tom Bailey and Will Williams took just 45 minutes to complete a 123-run LV=Insurance County Championship victory over Surrey.
A century by Jamie Smith has given Surrey a chance of making history in the LV= Insurance County Championship.
Sir Alastair Cook struck his 74th first-class century as Essex took advantage of perfect batting conditions in their County Championship clash with Somerset.
Durham clinched a dramatic one-wicket victory over Yorkshire with injured last man Brydon Carse hitting the winning runs.
Warwickshire underlined their County Championship title-chasing credentials by completing a four-wicket win over fellow challengers Essex inside three days.
England seamer James Anderson received treatment for a "minor issue" during Lancashire's County Championship match against Somerset.
Seamer Tim Murtagh claimed a 10-wicket match haul to top 1,000 wickets in all formats for Middlesex as they comfortably beat Kent in the County Championship.
Middlesex secured their first win of the season with a thrilling four-wicket victory over Nottinghamshire at Lord's with an over to spare.
England opener Zak Crawley hit a superb 170 to help Kent to 342-7 on day three of their County Championship clash against Essex at Canterbury.
James Anderson clinched the 54th five-wicket haul of his first-class career before Lancashire opener Keaton Jennings hit an unbeaten century.
England opener Ben Duckett notched a first hundred of the season on the opening day of Nottinghamshire's County Championship match against Middlesex.
Ollie Pope and Dom Sibley shared an unbroken 193-run second wicket partnership, as Surrey beat Hampshire by nine wickets at the Kia Oval.
James Anderson warmed up for this summer's Ashes by dismissing former England captain Sir Alastair Cook in his first County Championship appearance for 11 months.
James Anderson, Stuart Broad, Steve Smith, Marnus Labuschagne and - fitness-permitting Jonny Bairstow will enjoy some red-ball action ahead of the Ashes summer.
Fewer points will be awarded for draws in the County Championship to encourage the attacking cricket that has revolutionised England's Test team.
Check out the fixtures for the LV= County Championship in 2023, with the season running from April 6 until September 29.