Lancashire 131 (Harmer 5-41) and 25 for 6 (Snater 4-6) lead Essex 107 (Cook 40, Bailey 5-36) by 49 runs
Lancashire's coach Glen Chapple condemned the pitch as unfit for first-class cricket on a day of utter carnage as 26 wickets fell on a controversial surfce at Chelmsford.
Simon Harmer, who had bowled just 23 overs in two months since his last appearance for Essex in late July, returned from a largely inactive stint with South Africa to claim his sixth five-wicket haul of the summer to take his tally past fifty for the fifth time in six seasons. But while his 5 for 41 helped skittle Lancashire for 131, Essex struggled initially to capitalise in what is essentially the bronze-medal match to decide the finishing order in the LV= Insurance County Championship.
Lancashire seamer Tom Bailey matched Harmer's efforts by taking 5 for 36 as Essex were dismissed for 107. Only Alastair Cook's resolute 40, the highest by anyone on an extraordinary day, prevented Lancashire eking out a bigger first-innings lead than the 24 runs they managed.
However, that was not the end of the strange affair. When Lancashire batted for a second time in the evening gloom, Luke Wells was bowled first ball by Sam Cook before Shane Snater had three lbw appeals upheld in four balls to account for Keaton Jennings, Steven Croft and Dane Vilas.
When Cook then had Josh Bohannon caught behind Lancashire were reeling on four for five. And that became worse when Snater took a fourth wicket, his sixth of the day, knocking over George Balderson's stumps. By the close, at 25 for six, Lancashire's lead was a precarious 49.
Essex spinner Simon Harmer said: "For 26 wickets to fall in a day is unprecedented, but I think if you look back at some of the dismissals a lot of them were batter-error. So it wasn't all down to the wicket."
Lancashire were less forgiving as Chapple made little effort to temper his criticism.
"The lads are in really good form, having really good seasons, trying their best and desperate to try and win a game. They've just found the pitch unplayable. I thought we scrapped brilliantly to get to where we did to be honest.
"The surface of the pitch looks poor. The ball is coming off different every time, if you watch the batters they can't lay a bat on it. Ultimately we've got to fight and try and get as many in front as we can and see what happens to the pitch in the remaining part of the game. Obviously we had to bat under lights and that's exacerbated the movement. We've got players who couldn't hit the ball tonight. It's a really tough pitch.
"Sometimes pitches look different and you don't know, or assume anything, we just prepared to play as well as we could. But we needed to bat first because the surface isn't really intact. It's got foot-holes and holes in it, so we know it could potentially get worse. But we weren't expecting it to play like that.
"I think for the first three-quarters of the game there was a ball with your name on it, that was a given, but for the last 30 minutes it was completely ridiculous. Is it an acceptable pitch for first-class cricket? Absolutely not, no way, shape or form. We're here for four days to play a game of cricket and that's no good enough.
"We don't want our supporters to think we've thrown the towel in, we absolutely haven't. We want our supporters to know we're trying to the very end. Days like this are really annoying, simple as that."
Lancashire, who won the toss under leaden skies, were all out first time around three-quarters of an hour after lunch. Snater started their demise with his first ball, beating the outside of Wells's bat and rapping the off stump. The first-wicket stand of 25 turned out to be the largest of the innings, and second-largest of the game to date.
Snater also removed Lancashire's other opener, Jennings, at the start of his fourth over when an uncontrolled inside edge ballooned into the covers. In between, Cook, who had switched to the Hayes Close End to accommodate Snater, trapped Bohannon lbw to one that kept low.
Harmer's magisterial entrance was delayed until the 18th over and he bowled unchanged from the River End until Lancashire's brittle resistance was ended. Croft reverse-swept him for four before he rediscovered his range and sent one skidding through to claim Vilas lbw.
Croft hung around for a time before he chanced another reverse-sweep, realised his error, tried to rectify it and dabbed the ball to the diving Alastair Cook at slip.
Harmer went to lunch with a third scalp under his belt when Balderson injudiciously left the last ball before the break and was another lbw victim.
Lancashire were seven-down soon after the interval when George Bell marked his first-class debut by attempting an extravagant drive at Cook and was bowled. Will Williams did not last long before he was struck on the pad by Cook with bat nowhere near ball.
The innings was wrapped up in the 40th over - with Bailey unbeaten on 24, the highest of the innings - when Parkinson edged to slip to give Harmer his 29th five-wicket return in six seasons for Essex.
Essex's reply followed a similar dreary pattern. Nick Browne went third ball when he tried to whip Bailey through the onside and was lbw. Next over Tom Westley shouldered arms to Williams, turning to see his off-stump pegged back, before Bailey had Lawrence playing all around a delivery to depart lbw.
The procession back to the pavilion continued. Balderstone removed Matt Critchley with his fifth ball, Hartley taking the catch at head height, to his right, at third slip.
Feroze Khushi batted brightly before he dragged the first ball after tea from Parkinson on to his stumps. Adam Rossington, meanwhile, fished recklessly outside off-stump and kept walking.
Alastair Cook had watched the wickets tumble, but after holding up his end for 98 balls, he was seventh out, pinned plumb on his back foot by Bailey. Essex's innings finished seven overs later as Snater, Harmer and Jamie Porter departed in quick succession. That, though, was not the end of a bizarre day, not by a long way.
