Root spent last summer's series victory against Australia opening the batting alongside captain Alastair Cook, and was expected to continue there in the impending rematch.
But Michael Carberry has supplanted him at the top of the order, with a century and two 50s in England's three warm-up matches.
Root has been in form too, already making himself at home in the middle order with back-to-back half-centuries - against Australia A last week and in the first innings of England's seven-wicket win over an Invitational XI at the SCG.
After the tourists had beaten the rain in Sydney on Saturday - by seconds before a final downpour which would have brought a stalemate - Root made it clear he has no problem dropping down the order.
"I'm not that egotistical," said the 22-year-old Yorkshireman.
"I just want to represent England.
"To get an opportunity to bat down the order is a different challenge, but one I'm really looking forward to.
"Playing for England is the main thing for me."
England prevailed here thanks to Carberry's 50, in pursuit of a victory target of 148 after bowling the Invitationals out for 261.
Boyd Rankin and Steven Finn each finished with three wickets, the Ulsterman the more impressive and less expensive, while there were seven catches in the match for Jonny Bairstow.
He was deputising for injured wicketkeeper Matt Prior, who tore his calf in Hobart last week and is just back to light practice in the nets in the hope he may yet be fit enough to return for next week's first Test in Brisbane.
In England's final warm-up match, their sternest opponent was the Sydney weather - and they just got the better of it thanks to some late urgency from Ian Bell, in an unbroken half-century stand with Jonathan Trott.
Root, who had an x-ray after being hit on the finger in his first-innings 75 but was cleared of any break, was not part of the final push this time.
He is confident he will be able to lend a hand again in his new role when required.
"The basics are pretty similar," he said.
"There is still a guy 22 yards away throwing a ball at you.
"The second new ball is another challenge - and if that opportunity comes I hope I can manage it well and do a job for the team."
Root made one big hundred, and a half-century in the last Test, from his 10 Ashes innings as an opener on home soil.
"I definitely learned a lot from it and got a lot things out of it, and there are parts of my game I've worked hard on from last summer," he said.
"I hope I can become a better player for it."
In the meantime, he has no beef with Carberry's elevation.
"If you look at Michael Carberry's tour so far, he has played exceptionally well and scored a huge amount of runs and been in very good form," said Root.
"It's hard to ignore that. As far as the team is concerned it's very exciting."
Invitationals Test batsman Ed Cowan has seen Root open, when the pair were in Ashes opposition at Trent Bridge last summer, and bat down the order here.
He said: "I like the look of Joe Root.
"I think it's certainly an easier place to bat at number six, than opening the batting.
"He's an opening batsman by trade, so he'll want to open the batting.
"But if that's the difference between him being in the team or not in it, I'm sure he's happy to bat at six.
"It's a good place to learn about Test cricket.
"There's nowhere to hide at the top of the order, and it was a bit of a baptism for him against some high-class fast bowling in England."
Cowan also shared his thoughts on Kevin Pietersen - who made 57 and six in this match - and England's attempts to work out whether Rankin, Finn or Chris Tremlett should be their third seamer at the Gabba.
He has no doubts Pietersen will rise to the occasion.
"He's a big-game player," he said.
"I've played tour games against Kevin a few times now, and it's a warm-up for him.
"The main course is next week.
"I don't think he'd really care how many runs he got this week, or last week, or the week before. He'll turn up and expect to dominate next week."
Cowan was equivocal about Rankin and Finn, however - "they were probably too short all game" - and believes England need Tim Bresnan fit again as soon as possible.
"I think that third bowler, until Tim Bresnan comes back, will probably be the one issue that keeps popping up.
"I just think Bresnan's a massive player for them.
"He's a bit of an unsung hero. He bowls a huge amount of overs, never really gets hit out of the attack, takes big wickets - and as we saw during the last Ashes series, he scores some really important runs.
"That's a huge 'out', and I think Australia will look to exploit that third seamer."
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