Oliver Hannon-Dalby and Chris Rushworth both took four wickets as Warwickshire beat Essex for just 126 at Edgbaston.
But Essex point guard Jamie Porter then retaliated by pulling out both Warwickshire openers before the close to leave the Bears struggling 17-2.
Rushworth continued the blistering start to his Bears career on a rainy opening day in which 12 wickets fell after the delayed start at 2.30pm BST.
The former Durham pacemaker, in just his fifth game for Warwickshire, has now taken 26 wickets after finishing with 4-28, three-quarters of which came in a maiden triple-wicket in the last before tea .
From 76-2 Essex then crumbled as Hannon-Dalby followed in the final session with 4-21, to take him past 450 wickets in all formats.
After Warwickshire captain Will Rhodes won the coin toss for the first time this season, Essex batters found life difficult in wet and seam-prone conditions, with only skipper Tom Westley lasting longer one hour to reach the highest score with 47.
Rushworth, fresh off their dazzling 7-38 win over Hampshire last week, trapped Alastair Cook’s leg before the wicket with an inswinger.
Then Hasan Ali, recalled in place of rested England all-rounder Chris Woakes, struck in with his fifth ball when Nick Browne peeked up the leg and wicketkeeper Michael Burgess took a nice one-handed catch at full length.
Westley and Dan Lawrence added 52 in 12 overs before Rushworth struck three times in one over. Lawrence chipped the first ball on top, Matt Critchley narrowly survived second and third then edged fourth to Rob Yates at the slide and Michael Pepper fell to sixth.
Hannon-Dalby then took over, ending Simon Harmer’s stubborn 39-ball resistance with a dramatic furniture redesign.
Doug Bracewell then slipped slightly and Westley was taken to further cover and, after Hasan returned to trap Sam Cook, Hannon-Dalby hit Shane Snater’s stump.
But Essex inflicted immediate damage when Rob Yates was trapped on the first ball by Porter, who added a second wicket with the last ball of the day when Alex Davies took the third slip.
Report provided by the ECB Reporters Network.