Hampshire slumped to 18-5 - losing five wickets for no runs in 17 balls - as Essex ran riot in their Specsavers County Championship match.
Alastair Cook continued his outstanding early-season form while there was an injury scare for James Anderson.
Essex and Worcestershire discovered their prospective semi-final opponents early after a rain-hit final round of South Group fixtures.
Colin Ingram hit a third hundred for Glamorgan in the Royal London One-Day Cup in their 15-run win over Kent.
James Vince's 178 for Hampshire proved in vain as they slipped to a three-wicket defeat to Glamorgan in the RL One-Day Cup.
Alastair Cook's century helped Essex to a tense 10-run victory over Sussex in the RL One-Day Cup despite a Jerome Taylor hat-trick.
Lancashire won their first game of the Royal London One-Day Cup as Steven Croft's stunning 127 helped them beat Warwickshire.
Alastair Cook scored his 10th career List A century to guide Essex to a 29-run win over Gloucestershire in the Royal London Cup.
Kent's Alex Blake hit an incredible 46-ball ton but was still on the losing side as Somerset chased down 353 in the Royal London One-Day Cup.
Gloucestershire claimed an improbable Royal London One-Day Cup win over Middlesex on Sunday, as Somerset and Surrey also won.
Rob Key previews the Royal London One-Day Cup with Warwickshire looking to defend their crown as the white-ball season begins.
Lancashire clinched a comeback win over Somerset on day four of their County Championship clash, skittling the visitors for 130.
The 2017 Royal London One-Day Cup starts on Thursday, test your knowledge on the tournament with our 10-question quiz...
Liam Livingstone starred for Lancashire while Gary Ballance held Hampshire up in their County Championship Division One victory bid.
Joe Root and Jonny Bairstow registered single-figure scores as Yorkshire's top order capitulated against Hampshire at the Ageas Bowl.
New England captain Joe Root returned to action for Yorkshire at Hampshire,
where home skipper James Vince hit a century.
Joe Root will play his first innings in England since being appointed Test captain when Yorkshire take on Hampshire.
Essex are the second county to announce they will refuse to endorse the ECB's proposal for a new eight-team T20 competition.
Alastair Cook struck a magnificent century as Essex successfully chased down 225 to beat Somerset on day three in the County Championship.
Shivnarine Chanderpaul hit 182 as Lancashire dominate day two of their Specsavers County Championship Division One clash against Surrey.