Just as the first stage of the County Championship approaches its climax, 15 of the country’s very best first-class cricketers will leave their counties to join up with the England Test squad.

With four rounds of the group phase to go – sides have either three or four fixtures remaining – none of the six qualification spots for Division One are sealed.

Northern powerhouses Lancashire and Yorkshire currently occupy the top two spots in group three and both possess a game in hand over the chasing pack. At the time of writing, they look the most likely teams to qualify for Division One at this stage.

The top five in group one are all within 26 points of each other while the same points margin encompasses the top four in group two.

Here’s a look at how the counties will be affected by the absence of the England players:

Three Test squad members missing

Surrey

They will be without three of their top six – Rory Burns, Ollie Pope and Ben Foakes – for their upcoming home fixture against group two table-toppers Gloucestershire, a fixture that Surrey could really do with winning to close the gap between themselves and the top two. Will Jacks, Laurie Evans and Ryan Patel are three of the likely replacements – a handy group to have at your disposal – but losing two of the country’s leading run-scorers in Burns and Pope will always be a blow.

Their IPL stars – Jason Roy and the Currans – will also be absent, leaving them some way off their first choice XI.

Burns, Pope and Foakes are likely to be back in time for their final two group two fixtures against Hampshire and Somerset, but their England white-ball players will almost certainly miss the fixtures to join up with the England squad for the series against Sri Lanka and Pakistan. As well as the aforementioned IPL trio, this may also include Reece Topley who has impressed with the ball in this year’s County Championship.

Two squad members missing

Somerset

Craig Overton and Jack Leach are big misses on paper. Overton has arguably been the player of the summer so far while no English spinner has been as consistent wicket-taker as Leach over the past five years.

That said, they’re well equipped to manage their absence. They have a platoon of seamers ready to deputise for Overton while Leach’s absence can be mitigated by the inclusion of either Roelof van der Merwe (32 first-class wickets at 19.46 since the start of the 2017 season) or the impressive young all-rounder Lewis Goldsworthy.

Warwickshire

They’ll be without Olly Stone and Dom Sibley for their upcoming games against Derbyshire and Durham, while Chris Woakes, in the IPL, will also be unavailable. They’re big losses but the county have coped well with those three missing a sizeable chunk of the season so far – the trio have only played seven out of a possible 18 appearances between them. Warwickshire have an impressive pool of seamers to draw on; Craig Miles and Liam Norwell have been in and out of the side this season while George Garrett is another young quick worth keeping an eye on.

One squad member missing

All of Kent, Yorkshire, Sussex, Lancashire, Nottinghamshire, Gloucestershire and Durham will be missing just a single player each for the next two rounds of games.

Last two rounds of games

The last two rounds will coincide with England’s ODI World Cup Super League series against Sri Lanka and Pakistan. Eoin Morgan suggested over the winter that he will be without England’s Test regulars for those outings. Those squads have yet to be announced. Lancashire could possibly be without three of their red-ball regulars in Matt Parkinson, Saqib Mahmood and Liam Livingstone, especially if England don’t pick a first choice squad.

Availability after the division split

As it stands, the England-India Test series is set to be played from August 4 to September 14, dates that would rule England’s Test players out of three of the four rounds of games. The flip-side of this is that the England white-ball players not currently involved in the Test set-up should be available for the season run-in (unless a rescheduled IPL gets in the way).  If that happens, Yorkshire, with Dawid Malan and Jonny Bairstow back in their ranks, would be the major beneficiaries.