Lancashire 36, Eastern Counties 10
A place at Twickenham for the final of rugby union's County Championship is on the line next Saturday.
Lancashire take on Cheshire at Sedgley Park, with the winners gaining a place in the final of the Bill Beaumont Cup at Twickenham.
While the Red Rose team were winning at Fylde's Woodlands Memorial Ground, Cheshire were preserving their own 100 per cent record with a 29-7 victory over Yorkshire.
Lancashire take on Cheshire at Sedgley Park for the right to appear in the decider at the game's headquarters on May 29.
As Lancashire manager Steve Rigby, the former Fylde prop forward remarked: "We now play Cheshire in what can rightly be called a semi-final.
"So it is winner-takes- all, which is in many ways the way we would prefer it.
"We don't want to put permutations in the lads' heads - we want to know that it is win or bust.
"We have been in this sort of position before where we needed to make a statement."
In the match against Eastern Counties, Lancashire were well on top in the first half crossed for five tries in the space of 27 minutes, with only one by way of reply to establish an unassailable 31-5 advantage.
But they slackened off appreciably in the second period and their sole try in that half was after 71 minutes.
It was drab in the extreme in the second half with little in the way of excitement, as opposed to the first half try-fest when Lancashire went through their paces.
As Rigby remarked: "We thought the game was won and we started to try and play sevens rugby.
"That was disappointing because we could have improved our points difference significantly."
Lancashire took the lead after five minutes through hooker Mark Darlington, a one-time Fylde player, marking his return to the Woodlands in exemplary style as he barged through after being released by Gareth Rawlings.
Next up after that unconverted try, centre Chris Briers tested the stretched Eastern Counties defence with a piercing run through the middle following up good work by scrum-half Jordan Dorrington.
Lancashire's dominance continued and a rolling maul pinned the visitors back towards their own line - under severe pressure, visiting number eight John Wedlock was yellow-carded.
Anthony Bingham went for a narrow gap along the left-wing, but was just squeezed into touch as Lancashire piled on the momentum in a one-sided opening to this contest.
Lancashire scored their second try on 16 minutes in curious fashion through fly-half Chris Johnson.
At first referee Will Halford signalled that Johnson had been held up over the line, but after the intervention of the touch-judge the main official changed his mind and awarded the try, goaled by Johnson.
Two minutes later, Lancashire crossed again.
Lewis Allen, once briefly of Fylde, embarked on a superb break that tore the Eastern Counties' defence apart - he then continued the move by managing to slip out a pass to Dorrington, who weaved his way over for touchdown goaled by Johnson (19-0).
Undeterred by three tries in quick succession, Eastern Counties came back doggedly and after a series of attacks on the Lancashire line, scrum-half Mike Gillick dodged through on the blind-side down the right for a try, which was unconverted.
Lancashire's response was immediate and telling as Bingham made the most of acres of space on the left-wing as he side-stepped over the line in swift fashion (24-5)
Bingham had a big hand in the home side's next try - he turned defence into attack with a penetrating run from deep and Niall Crossley, doing well to keep up with him, finished off the job with a try, which Johnson converted (31-5).
Eastern Counties' woes continued when back row forward Tom Ranson was sin-binned.
Excellent work in which Johnson, Chris Briers, Bingham and Dorrington cut a swathe through the visitors' defence left East Midlands scrambling by desperately to cover as Lancashire tried to turn the screw.
Eastern Counties drew first blood eight minutes into the second half when left-wing Lawrence Hutchinson evaded a last-ditch tackle by Allen to score in the corner (31-10).
Bingham lost his footing at a vital time as Fylde launched a sweeping, cross-field attack in numbers as Lancashire sought their first try of the second half.
Briers passed up a good chance for Lancashire when cutting back inside rather than linking up with two players on the outside in plenty of space.
On 61 minutes Dave Fairbrother's sin-binning reduced Lancashire to 14 men after he was pinged for a no-arm tackle.
Lancashire, still seeking their first try of the half, were denied when Bingham was bundled into touch after a quick release-pass by Adam Lewis.
On 71 minutes Lancashire finally broke their second half duck - Dorrington pulled off a sleight-of-hand pass through his legs and Scott Rawlings took advanatge of such opportunism and touched down
Lancashire (all Fylde except where stated) Allen (Preston Grasshoppers) Crossley (Hartpury College) Briers, S Rawlings, Bingham, Johnson, Dorrington; Griffiths, M Darlington (Chinnor) Lewis, McGowan (Caldy) Tomlinson (Preston) Nugent (Bergerac) Stewart, G Rawlings. Replacements: Bitchall, A Darlington (Chinnor) Maher, Fairbrother, Goodman, Moulding (Preston) Wilkinson.