Will Mitchell Starc return?
Australia sorely missed their spearhead's express pace and bounce on a flat MCG pitch in the drawn fourth Test. The left-armer offers an element of variety in the hosts' attack and is renowned for his ability to clinically clean up the tail. Starc, who did some fitness and running work on the field during Saturday's lunch break, will be racing the clock as he recovers from a bruised heel.
England opener Alastair Cook acknowledged just how influential the addition of Starc would be to Australia's side after the Melbourne draw.
"The balance of your attack to have that different angle, as a batter it messes a little bit with your angles and stuff," Cook explained. "In an ideal world you'd like to have any left-armer because he changes batting. You've got a different angle over and around. That variety is quite important."
Which tweakers can turn the game on its head?
Nathan Lyon has been one of Australia's best bowlers throughout this summer and should trouble England's left-handers in Sydney, on what is expected to be a surface that will take spin. The visitors could axe off-spinning allrounder Moeen Ali, who has struggled with the ball and been dismissed six of seven times by Lyon.
Leg-spinner Mason Crane could debut for England at the same ground where he played a Sheffield Shield game for NSW, while Ashton Agar has been added to Australia's squad ahead of the likes of Jon Holland, Mitch Swepson and Steve O'Keefe.
"I think the biggest advantage of the BBL is the pressure and the crowds," Agar told reporters on Sunday, having returned aggregate figures of 1-59 from 12 overs (economy rate 4.92) in three games for the top-of-the-table Perth Scorchers so far in BBL|07.
"You've got batters trying to take you down, you have to bowl really well and you have to have good control over your length and variations.
"I actually think it’s really good preparation for a Test match.
"That may sound funny but there are certain things that, when you step into a Test environment, are really similar between BBL and Test cricket."
Will Australia collapse again?
Steve Smith's side enjoyed a productive first day of the fourth Test and were in the box seat to build an imposing total. Instead they lost 7-67, stumbling to be all out for 327 on the second morning. Josh Hazlewood lamented "lazy" dismissals. Coach Darren Lehmann was likewise unimpressed, saying his charges fell approximately 100 runs short of what would have been a strong first-innings total.
Alastair Cook went on to spearhead an emphatic fightback in his record-breaking knock of 244 not out to put England in a box seat and make the collapse look all the more concerning given the flat nature of the pitch.
Most alarmingly for the Australians, it's not the first time it has happened recently on home soil. In Adelaide against England, Australia were rolled for 138 in their second innings, while last summer, they lost 10-86 in Perth against South Africa after a 158-run opening stand, and were then bowled out by the same opposition for a miserable 85 in Hobart.
Can England stop the Smith juggernaut?
It's hard to imagine how, based on recent evidence. Smith is well placed to claim player-of-the-series honours in his first Ashes contest as captain. The world's best batsman produced man-of-the-match digs in Brisbane and Perth, with the latter a career-best 239 that effectively sealed the series win. Then in Melbourne his unbeaten 102 saved Australia the Test. The right-hander is the leading run-scorer in the series with 604 and will be keen to sign off with another big one on his home deck.
"He's playing really well and he's played very well over the past four or five years," Cook said after Melbourne. "Probably when we first saw him we didn't think he would turn out to be the player he has turned out to be and you've got to give him a lot of credit for the way he's worked at his game.
"He sticks to it for an incredibly long period of time. He's kind of setting a new benchmark for what can be possible."
Will Joe Root score a breakthrough hundred in Australia?
Root was dropped ahead of England's last Test at the SCG, and while that was never going to happen this time around, the captain would be disappointed with his output this summer. Root has passed 50 in three Test innings but failed to reach three figures on every occasion. The frustration showed after the skipper's dismissal at the MCG, when he flung his gloves and kicked the turf while walking off.
Root averages 52.45 across 64 Tests - the 27th highest batting average in history (min 20 inns) - but in Australia that drops to 30.64 across eight Tests, with four half-centuries, while he is yet to make a hundred Down Under.
The conversion rate mirrors a wider problem for the 27-year-old, who now had 13 hundreds and 35 fifties in his Test career. To put that into context, his opposite number Smith has 23 hundreds and 22 fifties.
Can Ricky Ponting's prediction come to fruition?
Ricky Ponting went one short of Glenn McGrath's traditional pre-series predictions and tipped a 4-0 series rout to the Australians. It was a bold call when most were predicting a tight series, however Ponting had his reasons.
"I’ve been a bit more outward than normal about this one because I honestly think that Australia will win really easily," Ponting told cricket.com.au in November. "My prediction is that I think it will be four-nil Australia, and I think the best chance that England have got will be in Adelaide where a night game, pink ball, the night time conditions will suit Anderson and Broad down to the ground.
"But if they don’t win that one, I can’t see them winning one."
Anderson indeed took five second-innings wickets in Adelaide - his first such haul in Australia - however England lost the Test, with Sydney their final opportunity to get on the board.
2017-18 International Fixtures
Magellan Ashes Series
Australia Test squad: Steve Smith (c), David Warner (vc), Cameron Bancroft, Usman Khawaja, Peter Handscomb, Shaun Marsh, Mitchell Marsh, Tim Paine (wk), Mitchell Starc, Pat Cummins, Nathan Lyon, Josh Hazlewood, Jackson Bird, Ashton Agar.
England Test squad: Joe Root (c), James Anderson (vc), Moeen Ali, Jonny Bairstow, Jake Ball, Gary Ballance, Stuart Broad, Alastair Cook, Mason Crane, Tom Curran, Ben Foakes, Dawid Malan, Craig Overton, Ben Stokes, Mark Stoneman, James Vince, Chris Woakes.
First Test Australia won by 10 wickets. Scorecard
Second Test Australia won by 120 runs (Day-Night). Scorecard
Third Test Australia won by an innings and 41 runs. Scorecard
Fourth Test MCG, drawn. Scorecard
Fifth Test SCG, January 4-8 (Pink Test). Tickets
Gillette ODI Series v England
First ODI MCG, January 14. Tickets
Second ODI Gabba, January 19. Tickets
Third ODI SCG, January 21. Tickets
Fourth ODI Adelaide Oval, January 26. Tickets
Fifth ODI Perth Stadium, January 28. Tickets
Prime Minister's XI
PM's XI v England Manuka Oval, February 2. Tickets
Gillette T20 trans-Tasman Tri-Series
First T20I Australia v NZ, SCG, February 3. Tickets
Second T20I – Australia v England, Blundstone Arena, February 7. Tickets
Third T20I – Australia v England, MCG, February 10. Tickets
Fourth T20I – NZ v England, Wellington, February 14
Fifth T20I – NZ v Australia, Eden Park, February 16
Sixth T20I – NZ v England, Seddon Park, February 18
Final – TBC, Eden Park, February 21