MELBOURNE: England head into the Boxing Day Test against Australia on Sunday knowing they must fix the mistakes that have blighted their tour or lose the Ashes series.

After a nine-wicket thumping in Brisbane and then crashing by 275 runs in Adelaide, Joe Root's team must win at Melbourne Cricket Ground to keep their slim Ashes hopes alive.

A boisterous crowd of about 70,000 is expected on the opening day of the Test.

As holders, Australia need only to avoid defeat to retain the urn.

The omens are not good for England -- the only instance of a team coming from 2-0 down to win the Ashes was Donald Bradman's Australia back in 1936-37.

In the first two Tests the tourists' batting, bowling and fielding were sub-standard and Root knows they must improve quickly.

"I am convinced we have what we need to win Test matches over here but we are not going to if we keep missing chances and don't give ourselves an opportunity to get into the Test match with the bat," he said.

Root blasted the side after Adelaide for "making the same mistakes", highlighted by a first-innings batting collapse and his bowlers hitting the wrong lengths, allowing Australia to build a big score.

But he also came in for sharp criticism himself, despite performing well with the bat and ball.

"What is the opposite definition of excellent leadership? There's a good chance it can be summed up by Joe Root's captaincy," ex-Australia skipper Ian Chappell said.

Another former captain, Ricky Ponting, also chipped in, blasting Root for not doing more to correct the bowling problems while the match was under way.

"If you can't influence your bowlers on what length to bowl, what are you doing on the field?" he said.

To rub salt in Root's wounds, Australian number three Marnus Labuschagne overtook him to become the world's number one Test batsman after his first-innings Adelaide century.

Australia riding high

English media reports suggest the visitors could make up to four changes with opener Zak Crawley potentially in for either Rory Burns or Haseeb Hameed and Jonny Bairstow taking over from Ollie Pope.

They are also likely to mix up the bowling unit again with speedster Mark Wood tipped to return, along with off-spinner Jack Leach, after England blundered by dropping him for Adelaide.

That would mean either Chris Woakes, Ollie Robinson or star quicks Jimmy Anderson or Stuart Broad missing out.

Coach Chris Silverwood is also under increasing pressure.

"I do believe I can turn it around," he told British media this week.

"We had a good talk in the dressing room, which was healthy and needed. I think there are some lessons to be learned. We have to be better -- it's as simple as that."

In contrast, Australia are riding high.

All of their top six made 50s in Adelaide, bar struggling opener Marcus Harris, while the bowling group performed admirably despite missing captain Pat Cummins and Josh Hazlewood.

Despite making just 38 from four innings so far, coach Justin Langer backed Harris to come good on his home ground in Melbourne in an unchanged batting line-up.

"He'll play in the Test, no worries about that," Langer said. "For him and for us we're hoping he plays well and gets a good partnership with Davey Warner in this Boxing Day Test match."

Cummins missed Adelaide after being a close contact of a Covid positive case, but he is set to return, while Mitchell Starc has a rib concern but should be fit.

There is less certainty around Hazlewood as he continues to recover from a side strain, while the fitness of Jhye Richardson and Michael Neser is being assessed.

That could open the door to a shock debut for experienced right-armer Scott Boland on his home ground after he was called into the squad as injury cover.