England's likely World Cup last eight opponents Australia laboured to victory over Georgia in swirling wind and rain.
With Typhoon Hagibis approaching Japan, the Wallabies took 22 minutes to open the scoring through Nic White's try.
Michael Cheika's side held a slender 10-3 half-time advantage and saw Isi Naisarani sin-binned for a high tackle.
A solo score from Marika Koroibete gave Australia a buffer but Alexander Todua crossed for Georgia before Jack Dempsey and Will Genia tries sealed the win.
The bonus-point victory takes the already-qualified Wallabies top of Pool D, although they will be overtaken by Wales if Warren Gatland's side avoid defeat by Uruguay on Sunday.
That would confirm a quarter-final meeting on 19 October with England, who will finish top of Pool C after their final group game against France was called off because of the extreme weather forecasted on Saturday.
Another yellow card and stuttering start
England head coach Eddie Jones is likely to be encouraged by the match in Shizuoka, with Australia's faults in this World Cup refusing to go away.
The Wallabies were not helped early on by losing full-back Kurtley Beale, who did not return to the field after a head-injury assessment.
But - having trailed at half-time in both of their opening two pool matches and played 20 of the opening 40 minutes against Uruguay with 14 men - Cheika's side again started sluggishly, making errors deep in Georgia territory to allow the Tier 2 side some brief respite out of their 22.
Scrum-half White - who will leave Exeter to rejoin the Brumbies Super Rugby franchise next summer - eventually burrowed over from close range to break the deadlock, but a high tackle from Tolu Latu gave Georgia a penalty and was a precursor to further indiscipline.
Five minutes later number eight Naisarani was yellow-carded for leading with his arm and making contact with the face of Giorgi Nemsadze - a fourth sin-binning of the tournament for the Australians, who were without Reece Hodge because of suspension.
There was a nice moment as Rob Simmons came off the bench for his 100th cap, but even despite the testing conditions and making 10 changes the Wallabies will be concerned at not being able to kill the game off until the closing stages.
Georgia compete but rarely threaten
Though qualification was beyond the Lelos in their first-ever meeting with Australia, third place in Pool D and a guaranteed spot at the 2023 World Cup were up for grabs.
It was a dogged display in Milton Haig's last game in charge, with Georgia's 201 tackles the joint second-highest tally in a World Cup match, behind only France's 205 against New Zealand in 2007.
Their fine defensive performance was spearheaded by veteran Toulon flanker Mamuka Gorgodze, who was playing in his 15th World Cup match, equalling the Georgian record set by Merab Kvirikashvili.
However, they struggled to make an impact offensively and lacked the tools to really harm the Wallabies.
Todua's try in the corner, after a fine run from Lasha Khmaladze, will at least live long in the memory and ensured they scored at least one try in each of their four pool stage matches for the first time.
What they said
Australia head coach Michael Cheika:
"The hit-out was good, having to dig in, work hard, get up off the ground, get into some tough stuff.
"It's how we wanted the game to go, we wanted to work like that.
"Our forwards stepped right up to it. We handled the Georgian scrum well, we scored a maul try... and the line-out worked.
"We did drop a bit too much ball. But I thought our carrying was strong, we just didn't have the finishing touch on a lot of stuff so we'll definitely put that on and we'll prepare that and be ready to finish the opportunities that will come next weekend."
Georgia head coach Milton Haig:
"We knew it was going take a toll in the second half.
"We had some opportunities in the second-half, but we couldn't get our set piece going.
"I can't fault the boys on how they put themselves about. I was really proud of them tonight, especially in defence."
Teams
Australia: Beale, Petaia, O'Connor, Kerevi, Koroibete, Toomua, White, Sio, Latu, Kepu, Rodda, Arnold, Dempsey, Pocock (capt), Naisarani.
Replacements: Uelese, Slipper, Tupou, Simmons, Salakaia-Loto, Genia, Lealiifano, Haylett-Petty.
Georgia: Matiashvili, Kveseladze, Kacharava, Sharikadze (capt), Todua, Khmaladze, Aprasidze, Nariashvili, Mamukashvilli, Gigashvili, Nemsadze, Mikautadze, Saghinadze, Gorgodze, Gorgadze.
Replacements: Bregvadze, Gogichashvili, Melikidze, Giorgadze, Tkhilaishvili, Lobzhanidze, Malaguradze, Mchedlidze.