Australia (26) 52
Tries: Gallen, Tate 2, Slater 3, Thurston 3, Inglis Goals: Thurston 6
Fiji (0) 0
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Highlights - Australia 52-0 Fiji
Billy Slater and Johnathan Thurston scored hat-tricks as Australia reached the World Cup final with a 10-try demolition of Fiji in Sydney.
The reigning champions were heavy favourites and Paul Gallen put them ahead with just a minute on the clock.
And they never looked back after going 22-0 ahead after just 16 minutes.
Although Fiji battled bravely, they were no match for the Kangaroos, Brent Tate ending up with two tries while Greg Inglis completed the scoring.
Australia will now meet New Zealand in Saturday's World Cup final and will be odds-on to retain their crown.
Ricky Stuart's side have yet to be fully tested so far, winning all their games and conceding just 16 points in the process.
The only downside to the semi-final win over the Fijians was the hip injury to New Zealand Warriors wing Tate, who is now almost certainly out of the final.
Fiji have been the surprise package of the competition but got off to the worst possible start against the Kangaroos, losing the ball on the second tackle of their first set of six with just 21 seconds gone.
Australia were clinical in their response, full-back Slater jinking his way through the Fiji defence before off-loading neatly for loose forward Gallen to crash over underneath the posts.
With the Fijians still reeling, Tate added a second try in the corner five minutes later after being released out wide.
The Aussies, breaking at will, were on the front foot again when stand-off Thurston burst through before streaking half the length of the pitch.
From the resulting attack, Slater beat two defenders to collect Thurston's cross-field kick for the third try after just nine minutes.
After Fiji had made a rare foray into the Aussie half, the Kangaroos showed how to turn defence into attack to score their fourth.
Skipper Darren Lockyer released Israel Folau, taking a heavy hit to the ribs in the process, before the centre then fired out a pass to Tate, who put on the afterburners to run in from inside his own half.
It was one of the last contributions from the NZ Warrior, though, as he pulled up injured with no-one near him.
Australia were strolling at 22-0 up but Fiji displayed their battling spirit and had the best of the rest of the half.
Guided by half-backs Alipate Noilea and Aaron Groom, they piled on the pressure but the Aussie defence was well marshalled and they mopped up everything that was thrown at them.
Australia then reminded the Sydney crowd who was boss with a try before the break.
Thurston scored three tries in just 10 second-half minutes
Slater finished off in the corner after a wonderful interchange between Thurston and hooker Cameron Smith.
The Kangaroos added another eight minutes into the second half, Slater securing his hat-trick and seventh try of the competition after being played in by Lockyer.
The game threatened to boil over in the middle of the half when the Fijians started producing some massive hits, Lockyer receiving the biggest when he was knocked backwards off his feet by a Jarryd Hayne shoulder charge.
But that was as exciting as it got as Australia restored order with two quick-fire tries from Thurston, the first coming when the North Queensland Cowboys star barged his way through three tacklers.
Thurston claimed his third with just eight minutes left after picking up a loose ball, while centre Inglis showed his pace to burst clear of the Fiji defence and touch down in the corner.
Fiji almost claimed the try their performance deserved right at the end, but Waisele Sukanaveita was held up over the line.
The result ends Fiji's memorable run while Australia will now rest their bruised bodies ahead of Saturday's final in Brisbane.
Australia: Slater; Monaghan, Inglis, Folau, Tate; Lockyer (capt), Thurston; Civoniceva, Smith, Price, Stewart, Laffranchi, Gallen. Replacements: Hunt, Fitzgibbon, Tupou, Kite.
Fiji: Hayne; Tadulala, Naiqama (captain), Millard, Uate; Noilea, Groom; Sadrau, Sukanaveita, Vonomateiratu, Sims, Koroi, Bukuya. Replacements: Storer, Bradley-Qalilawa, Tora, Wesele.
Referee: A Klein (Great Britain)