It jars that Sydney is a city of cricketing endings. Circular Quay, flanked by the shimmering Opera House and magnificent Harbour Bridge, is a place of inspiration. The fireworks of new year's eve signal spectacular renewal. Yet, the Sydney Cricket Ground is a place where the Australian greats wave goodbye. Shane Warne, Glenn McGrath, Justin Langer, Mike Hussey and David Warner are just a few to have taken their final bow in this grand old stadium. Usman Khawaja will do the same in the coming days.

England have had plenty of endings here, too, just not many that were planned. This century, 13 Englishmen have played the final Test of their careers on this ground – a lot when you consider England only come here every four years. Kevin Pietersen, Jos Buttler and Andy Caddick are among those to have not known an SCG Test would be their last. This Ashes series is not over, but there was an inescapable feeling that the third day of the fifth Test was the end of something.

This has been England's most disappointing tour of Australia in recent memory. A win in the finale, cutting the deficit to 3-2, would provide a rose-tint fitting of the pink day in Sydney. With a decent T20 World Cup, a few tweaks here and there, then maybe Brendon McCullum and the rest of the hierarchy would survive. A 4-1 scoreline more accurately reflects the cricket played, denies the opportunity to paper over the cracks and provides clarity for the way ahead.

In what was supposed to be England's big opportunity to finally win the Ashes down under, they have been thumped by an Australia team with a reserve bowling attack. This tour has ended like all the others – injuries, collapses in form and a selection trifle. England had planned to hit Australia with pace, only for part-time off-spinner Will Jacks to play as many Tests as Mark Wood and Jofra Archer put together. Matthew Potts was England's eighth-choice seamer for this tour and ended up opening the bowling.

There was no reserve opener or keeper to take either Ben Duckett or Jamie Smith out of the firing line. It has culminated in this – a sombre send-off in Sydney. Before Smith's all-time honker of a dismissal on the second day, England were 323-5 in their first innings. Despite a collapse and a Travis Head assault, the tourists were still in the contest as day three dawned.

But this was a terrible Tuesday, beginning with the most damaging session since the first drink was ordered in Noosa. Potts bowled like a man England turned their backs on in the home summer and Head hit the ball anywhere he pleased. Jacks was guilty of the worst drop on a tour where fingers have been bathed in butter. Michael Neser, Australia's nightwatchman, faced more deliveries than England's top three combined. England wasted two reviews on him and, when he was finally removed, Zak Crawley dropped Steve Smith. On it went into the afternoon.

Jacob Bethell looked like England's best spinner and bowled seven more overs than Jacks – the man chosen to bowl spin. Ben Stokes, England's best seamer, flogged himself with the old ball then gave the second new ball to Potts and Brydon Carse – England's worst seamers. Smith made a century, because that is what Smith does. The best since Bradman is the modern killer of England Ashes dreams, responsible for ending a few careers.

It is fair to argue it is unhealthy for English cricket to clear the decks after every failed Ashes expedition. England do not win here often. Lurching between leaders and methods is not a recipe for sustained success – ask Manchester United. But there also has to be an acknowledgement that the looseness and lack of detail in the current set-up cannot be allowed to continue.

There is a risk of harming the development of some talented young players, almost all of whom know no other approach to Test cricket. England's batters exist in a world without consequences and therefore exist in a world without responsibility. There have been three different bowling coaches in little more than a year, resulting in an attack that cannot execute a plan. Fielding drills are often limited to slip catching and Jamie Smith is rarely seen practising his keeping. McCullum's methods are ingrained and creating a culture is his super-strength.

He is suited to reviving an ailing team, just as he did with England almost four years ago. Perhaps, with ultra-hindsight, the perfect time for his departure would have been the end of the previous Ashes. He had turned the ship around and could have handed the reins to a more meticulous leader capable of taking England to the next level. Sydney is on track to be a 14th defeat in 28 matches since then.

It has been suggested McCullum could have additions to the staff imposed upon him. It is hard to see how any head coach is forced into a backroom shuffle without feeling undermined. Stokes has publicly supported McCullum, as he should. If Stokes has strong feelings about the identity of the coaching staff, he should be heard.

Surely the captain can see where his team have failed, and where they need to tighten up. The immediate future is not clear. England and Wales Cricket Board chairman Richard Thompson and chief executive Richard Gould have been in Sydney to see the grizzly ending. Director of cricket Rob Key will take as much accountability as McCullum and is of similar risk of losing his job.

This England regime has escaped criticism for previous results, often because mitigation has been found. England enforced the follow-on against New Zealand in Wellington in 2023 and lost, but it was lauded as a one-run classic. Falling 2-0 down in the Ashes of the same year was masked by the Jonny Bairstow stumping and fightback to 2-2. Series defeats in India and Pakistan in 2024 were explained by historical struggles batting against and bowling spin.

The disappointment of a 2-2 draw with India last summer was lost in the heroics of a one-armed Chris Woakes at The Oval. More than anything, evaluation of the Bazball era was reserved because this England management asked to be judged on this Ashes series.

That judgement is now. There is more cricket to be played, but this felt like an ending.