HAWTHORN has advanced to back-to-back Grand Finals in extraordinary fashion, coming from 20 points down at three-quarter time to defeat Geelong by five points in a gripping preliminary final on Friday night at the MCG.

Aided by their week's rest and a heroic 38-possession performance from Sam Mitchell, the Hawks booted the last three goals of the game to run out 14.18 (102) to 15.7 (97) winners.

Alastair Clarkson's men had looked in big trouble at the last change. 

They narrowed the margin with a goal early in the last term, yet they looked dead and buried when Josh Caddy gave the Cats what looked to be a match-winning 19-point advantage seven minutes into the last term.

But with Mitchell and Grant Birchall (27 possessions) leading the way, Hawthorn refused to give up, and late goals to Bradley Hill, Jack Gunston and Shaun Burgoyne powered them back into the lead.

Geelong's Travis Varcoe had the chance to level the scores with 30 seconds remaining, but his shot from 30 metres out on the run faded wide. It proved to be the last score of the game. 

The scenes at the end were extraordinary. Such was the noise made by the Hawthorn fans as their team surged forward one last time, the final siren seemed to go unnoticed.

It was Hawthorn's first win over Geelong since the 2008 Grand Final, snapping an 11-game losing streak to the Cats and burying the ‘Kennett Curse’. The Hawks will aim to win their first flag since that famous day when they take on either Fremantle or the Sydney Swans in next Saturday's decider.

Clarkson's side would have been stiff to lose, given it dominated the inside 50 count 64-42 and had 32 scoring shots to 22.

Along with Mitchell and Birchall, Brent Guerra was outstanding down back, while Gunston kicked four goals and Burgoyne finished with three.

The Hawks' performance was particularly meritorious given some of the team's biggest names were well down on their best.

Lance Franklin, who hyper-extended his right elbow in the first quarter, managed just 16 possessions and one goal, while Coleman medallist Jarryd Roughead had just 11 touches and went goalless.

Luke Hodge was also quiet.

Geelong, which was aiming to make it fifth Grand Final in seven seasons, would undoubtedly be gutted to lose in such fashion.

Steve Johnson was a standout, seeing off close attention from a number of Hawks to finish with 32 possessions and four goals.

Cats skipper Joel Selwood (23 disposals and a goal) was another key performer, especially during the third quarter when he started forward before moving into the middle and taking control.

With experienced stars Corey Enright (knee) and Paul Chapman (suspension) watching from the sidelines, youngsters Jordan Murdoch and Josh Caddy also stood up under pressure.

Murdoch slotted a brilliant right-foot snap with six seconds remaining in the third quarter, which gave the Cats their 20-point lead at three-quarter time.

Having started as the sub, Caddy was brought into the game midway through the third quarter in place of veteran backman Josh Hunt, who was having a very quiet night. 

The former Gold Coast Sun made a difference straight away and ended his stunning cameo with 12 possessions and a superb goal.

But it is the Hawks who live to fight another day.