Mohammad Amir and Sam Cook teamed up to leave Kent struggling as Specsavers County Championship Division One leaders Essex turned the screw at Canterbury.
Amir took three for 30 and Cook three for 25 to leave the home side on 125 for six by stumps on a rain-affected opening day.
Only Daniel Bell-Drummond with 55 and Ollie Robinson, who scored 35, made it to double figures in the 53 overs which were completed.
Second-placed Somerset endured a frustrating day as Rob Yates scored an unbeaten 139 – his maiden first-class century – to guide Warwickshire to 303 for four by the close of play.
Opener Will Rhodes provided valuable support, the pair putting on 153 for the second wicket before Craig Overton removed the former Yorkshire player for 82.
Luke Wood took five for 67 as Nottinghamshire skittled Yorkshire for 232 at Scarborough.
It could have been significantly worse for the home side had Jonathan Tattersall and Tim Bresnan not added 121 for the sixth wicket after they had slumped to 38 for five, Bresnan eventually going for 58 and Tattersall just eight runs short of a century.
Nottinghamshire will resume on 41 without loss with openers Ben Slater and Jake Libby having safely negotiated 17 overs.
Surrey all-rounder Rikki Clarke also claimed five wickets to help reduce Hampshire to 222 for seven at the Oval.
Clarke’s five for 52 did the bulk of the damage with one of his victims, opener Ian Holland, the only man to pass 50, although he departed having added just one more run.
In Division Two, Tom Bailey and Danny Lamb bowled leaders Lancashire into a strong position against Glamorgan at Colwyn Bay.
The pair took four wickets each as the home side were dismissed for 257 with Charlie Hemphrey making 56, on-loan debutant Samit Patel 54 and number 10 Lukas Carey an unbeaten 51 before the visitors reached 85 for the loss of Alex Davies.
Sussex seamer Ollie Robinson blew Middlesex apart with an eight-wicket blitz as the home side took full control at Hove.
Robinson claimed a career-best eight for 34 in 11 overs as the visitors were routed for just 75, and Sussex built upon their good start to establish a 53-run lead with seven wickets remaining.
Ryan Higgins claimed five Derbyshire wickets as Gloucestershire enjoyed mixed fortunes at Derby.
His five for 54, coupled with Josh Shaw’s three for 50, saw the home side succumb for just 200, although Gloucestershire lost opener James Bracey and Gareth Roderick to finish the day on 46 for two.
Northamptonshire reached stumps 46 runs adrift of Worcestershire with seven wickets in hand after Brett Hutton had ripped through the visitors’ batting line-up to record figures of six for 57.
Skipper Joe Leach’s unbeaten 53 spared Worcestershire’s blushes further as he and number 11 Josh Tongue put together a 10th-wicket partnership of 52, but a knock of 63 not out by Alex Wakely left the hosts in a promising position.
Opener Alex Lees blasted 181 to put Durham in control of their home match against lowly Leicestershire.
Lees’ contribution and 86 from Jack Burnham helped their side to 368 for five as the visitors endured a long day in the field at Chester-le-Street.