Australia are expecting the unexpected from an Sydney Cricket Ground (SCG) pitch that will shape, along with Mitchell Starc's sore foot, whether Ashton Agar plays his first Test on home soil.
Starc suffered a bruised heel during the third Ashes Test, during which he helped Australia claim an unassailable 3-0 lead in the series.
The spearhead was ruled out of the ensuing draw in Melbourne but is desperate to prove his fitness for the series finale that starts in Sydney on Thursday.
Left-arm spinner Agar has been added to what is now a 14-man Test squad. It's likely either Agar or Starc will replace Jackson Bird in the XI.
There may also be a temptation to rest Pat Cummins but the young gun has made it clear he wants to play all five Tests this summer, having become the most resilient member of the pace attack after almost six years of injury hell.
Australia hope the SCG pitch will not be anywhere near as flat as the docile MCG deck that earned criticism from both camps and many pundits.
"We'll turn up there and see what the wicket is," skipper Steve Smith said.
"You don't know what you're going to get in Sydney. One day it could be green, one day it could spin a bit.
"We've got all options there. We'll wait and see how we go."
Smith's home ground is among his favourite cricket venues in the world but that is for sentimental reasons rather than the centre strip.
Outgoing Gabba curator Kevin Mitchell Jr was presented with a gift by Smith on behalf of the team during the series opener.
Former SCG curator Tom Parker spent 20 years in the hot seat on the SCG roller but there are unlikely to be any similar tributes from Smith this week.
Parker retired earlier this year, giving Smith a public clip in response to the skipper rating his pitch as poor after a Sheffield Shield game last season.
The most recent Ashes contest in Sydney ended in a flurry of wickets and a whitewash but coach Darren Lehmann was unimpressed with the pitch.
"How do you reckon I would assess it? Words will get me in trouble here. It's disappointing, a three-day Test match," Lehmann said in 2014.
The SCG is yet to host a Shield game this season, having undergone its first full returf in seven years.
Smith wouldn't be drawn on Starc's hopes of playing in Sydney, saying he was happy he didn't play and do further damage in Melbourne.
"Which he could have on what was pretty flat wicket," he said.
Australia will take a conservative approach with the express paceman, who will be among their most important weapons on the upcoming Test tour of South Africa.
However, Starc's injury has improved dramatically in recent days.
The left-armer did some fitness work under the watchful eye of the team's doctor during the lunch break on day five of the fourth Test, hustling through his run-up then pulling out at the delivery stride.