Ravi Bopara and Tom Westley both hit hundreds as Essex responded superbly on day two of their LV= County Championship Division Two clash against Kent.
The right-handed duo shared an unbroken partnership of 229 as their side reached 253-1 on day two in response to Kent's 387.
Bopara reached 112 not out after recording his 24th first-class ton, but his first since May 2013, while 25-year-old Westley ended his 14-month wait for a three-figure score with an unbeaten 114.
Kent's last three wickets fell for 43 in the morning session, Ben Harmison returning to add 16 of those to the two he scored on Saturday before retiring hurt.
Nick Browne was dismissed for eight but Westley (114no) and Bopara (112no) made the bowlers toil thereafter.
At Grace Road, Derbyshire new-ball pair Mark Footitt (6-65) and Tony Palladino (4-62) combined to dismiss Leicestershire for 311 on day one.
Niall O'Brien top-scored with 89 and there were also half-centuries for Ben Raine and Josh Cobb as the Foxes recovered from 111-3.
Derbyshire, who announced on Sunday that key all-rounder Tim Groenewald will be leaving the club, responded with 12 for no loss in nine watchful overs before stumps.
Elsewhere, Alexei Kervezee top-scored with an unbeaten 65 as Worcestershire reached 175-4 against Hampshire, before bad light and rain ended the day's play one over after tea.
Wickets fell at regular intervals during the two sessions that were completed, with Hampshire seamer David Balcombe taking 2-26.