Warwicks made sure that Essex only added one run to their over night total to finish 150 all out but it looked a difficult target to beat as Warwickshire were soon in trouble.
Whilst CEO Colin Povey was busy fretting about the England game against Pakistan which starts at Edgbaston tomorrow, the team he has overall responsibility for, were losing wickets at a worrying frequency.
James Ord was out for one, skipper Ian Westwood could only add seven runs and Jim Troughton ten to see Warwicks on 35-3.
Darren Maddy and Rikki Clarke added 49 before Maddy was out for the top score of 39.
Tim Ambrose made only six before Clarke went for 36. Masters had Woakes caught for one before Bryce McCann mopped up the table for a four wicket haul and Warwickshire all out for 155, five runs ahead.
That slender lead was soon eradicated as Essex got to 33 before Pettini was caught behind by Tim Ambrose off the bowling of Boyd Rankin.
Neil Carter took the wickets of Bopara and Mickleburgh as Essex closed on 78-6.