A five-wicket haul from Graham Napier and Jaik Mickleburgh's unbeaten century enabled Essex to enjoy the better of the second day of their LV=County Championship clash with Leicestershire.
The hosts finished on 216-4 at Chelmsford in reply to a first-innings total of 365 from Division Two's bottom side.
Leicestershire resumed on 328-4 but Napier got rid of the overnight pair of Ned Eckersley (147) and Matt Boyce (54), and he went on to rip through the tail.
The all-rounder followed up his early successes by having Josh Cobb (4) caught before bowling both Anthony Ireland and Alex Wyatt for ducks.
It gave him figures of 5-77 from 20.3 overs and followed his 7-90 when the counties met at Leicester in their previous Championship match.
Napier's performance also came on a day when fellow paceman David Masters missed the action after being caught up in a traffic jam following a pile-up on the M25.
Mickleburgh and Hamish Rutherford put the Essex innings on a firm foundation with a stand of 61, before the New Zealander (24) was caught by Wyatt after offering a careless stroke to Ireland.
Greg Smith (8) quickly followed when he edged to Joe Burns in the slips to provide off-spinner James Sykes, who was making his debut, with the first Championship wicket of his career.
Owais Shah perished when he pushed forward against Wyatt to be caught behind just before the 100 was raised and Ryan ten Doeschate lazily drove Ollie Freckingham to mid-off.
Amid the setbacks, Mickleburgh grew in confidence and punctuated the field with several well-timed strokes as progressed towards his first century of the summer.
He eventually got there by cover driving Shiv Thakor to the boundary, his 13th, and by the close he had added another three boundaries to move to 121, with Ben Foakes with him on 25 at stumps.