|LV= County Championship Division Two, Chesterfield|
|Close, day one: Derbyshire 275, Essex 25-1|
|Derbys 2pts, Essex 3pts|
Essex's Graham Napier took four wickets to restrict Derbyshire on day one.
Essex, who dropped Monty Panesar from their squad, had early success as Derbyshire were 80-3, with Tom Moore (2-35) getting rid of both openers.
Wayne Madsen (90) and Wes Durston (74) put on 146 for the fourth wicket, but the latter had to retire after being struck on the helmet by Napier.
Napier ended with 4-44 as Derbyshire collapsed to 275 all out, before Essex closed 250 runs behind on 25-1.
Tom Westley was the only Essex wicket to fall, caught by Ben Slater off Mark Footitt for four.
The hosts, who had earlier seemed set for a large total with Madsen and Durston at the crease, lost their last six wickets for 49 runs.
Derbyshire elite performance director Graeme Welch on Wes Durston's injury:
"They didn't keep him in. He's got to be around people tonight to make sure nothing happens but he seems okay.
"The doctor has said he's fine and he just needs observing this evening."
Essex bowler Graham Napier:
"It's not nice to see a player taken off the field with an injury, but it opened up an end for us and we took advantage of that situation.
"It's a good pitch with good pace and a bit of bounce.
"If you get the ball in the right area something is going to happen, so we have to be mindful when we bat."