How will England's Test middle order look in New Zealand this winter?

Trevor Bayliss' exit means England will head on their Test tour of New Zealand in November with a new coach - possibly an interim one - but that is unlikely to be the only change.

England's middle order - the engine room of the side for so long - is under the spotlight with it not quite firing as it once was, save for Ben Stokes, who was in dazzling form this summer.

England reverted to a 4, 5, 6, 7, 8 of Joe Root, Jos Buttler, Stokes, Jonny Bairstow and Moeen Ali after slipping 2-0 down in the West Indies earlier this year, wicketkeeper Ben Foakes the fall guy as he lost his place in the side and Bairstow retook the gloves.

"Four through to eight has been successful in the past and we've gone back to that. We've known for a while that those players are our best," Bayliss said at the time.

The switch paid off in the sense that England won the final Test to avoid a whitewash in the Caribbean, but that quintet has been shifted again back on home soil.

Ali has been dropped from the side after a lean spell with bat and ball, Root batted at No 3 throughout the drawn Ashes series, Stokes stepped up to No 4 in the final Test against Australia when a shoulder injury forced him to play as a specialist batsman, while Buttler and Bairstow have flipped between 5, 6 and 7. It's hard to keep up with it all.

Playing Bairstow as a specialist batsman at No 5 must now be in England's thinking as they look to get the best out of one of their most talented but currently under-performing players.

Since Bairstow was given back the wicket-keeping position in February, he has averaged 18 in Test cricket. No hundreds, one fifty and two ducks in 13 innings. He has made very few mistakes with the mitts but his form with the bat has fallen off a cliff.

Bairstow's stats suggest he is more comfortable playing as a keeper-batsman. He averages 37.85 in 48 Tests as a keeper-batsman but that drops to under 30 in 21 Tests when he is playing as a batsman alone, so perhaps it is slightly fanciful to suggest he is bound to score more heavily playing sans gloves at No 5.

Bairstow has, of course, had a draining summer - he was a fulcrum of the triumphant World Cup campaign and has since played six Tests in eight weeks. He must be knackered.

Perhaps all it will take is a break and he will rock up in Mount Maunganui for the first Test against New Zealand revitalised, having more than likely been rested for the five-match T20I series that precedes it.

But it would be surprising if there was not a deep debate among the selectors about tweaking Bairstow's role. It's not as if England are short of keepers.

Buttler - who rediscovered his form at the back end of the Ashes, topping out with 70 at The Oval - could take the gloves. Alternatively, he could stick at No 6 with England recalling Foakes, who is generally considered the best gloveman of the three and the best in the world by Surrey supremo Alec Stewart.

Foakes is also very adept with the bat. He scored a century on his Test debut in Sri Lanka and his first-class batting average is almost six runs higher than Buttler's, with both having played more than 100 matches.

You can also add Ollie Pope into the middle-order conundrum.

The 21-year-old looks the next man in line after being called up as a concussion replacement for Jason Roy ahead of the Headingley Test and scoring an unbeaten 221 for Surrey in the County Championship since returning from a dislocated shoulder he suffered in April.

Pope had a taste of international cricket when he played two Tests against India in 2018, impressing fleetingly with three double-figure scores in as many innings. He looks set to go to New Zealand and push for a spot at No 5 or No 6.

If England play Pope and Foakes and it becomes one from two between Bairstow and Buttler then recent form would suggest Buttler would get the nod - he is averaging almost 36 since his recall last summer, while Bairstow is averaging under 25 in that time.

Pope's Surrey team-mate Sam Curran is also an option at No 7 if Stokes' promotion to No 4 becomes permanent. He adds variety with his left-arm seam and spark with his lower-order batting, though that would likely mean no Foakes and one of Bairstow or Buttler behind the stumps.

Watch England's tour of New Zealand, which features five T20Is and two Tests, live on Sky Sports Cricket in October, November and December.

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