|LV= County Championship Division Two, Chelmsford (day one)|
|Derbyshire 148: Thakor 44, White 38 not out, Porter 4-28|
|Essex 108-0: Cook 50 not out, Browne 47 not out|
|Derbyshire 0 pts, Essex 3 pts|
England captain Alastair Cook hit an unbeaten 50 after Jamie Porter claimed a career-best 4-28 as Essex took firm control against Derbyshire.
Seamers Porter and Jesse Ryder (2-55) ripped through the visitors' top order to quickly reduce them to 25-5.
Shiv Thakor (44) And Wayne White (38no) led the fightback, putting on 60, before Derbyshire were all out for 148.
Cook and Nick Browne (47 not out) then shared an unbroken century stand as Essex reached 108-0 at the close.
The left-hand duo were able to advantage of improving batting conditions, with Cook continuing the good form he displayed in the recent Test series against New Zealand.
Their performances followed Porter's penetrative spell of seam bowling that bettered the 4-59 he registered against Gloucestershire in May.
A total of 13 overs were lost during the day due to the weather, but Essex have still put themselves in a strong position to pull away from the bottom of the County Championship Division Two table, trailing by just 40 runs with all first innings wickets intact.
Essex batsman Alastair Cook:
"We had a bit of luck in winning the toss and it proved to be good toss to win, but it clearly wasn't a 148 all out wicket.
"We were a bit sloppy in the field and I cost Jamie Porter his first five-for dropping a catch, which I am sorry about, but then Brownie [Nick Browne] and myself played quite nicely to get a good partnership going.
"Now we have to build on that to improve our position and we have the opportunity to build a big first innings score."
Derbyshire all-rounder Wes Durston:
"They were perfect conditions to bowl, which assisting some good bowling. It proved a very disappointing first session-and-a-half.
"Their openers played pretty well and we haven't had chances go to hand, so it's been frustrating."