MELBOURNE is through to next week's preliminary final after an unbelievable three-point comeback win over Greater Western Sydney on Saturday.

The Giants looked in complete control midway through the last quarter with a 15-point advantage until the Demons slammed on the last three goals, the last from young forward Lily Mithen – her second - with 25 seconds left in the final term.

04:36

AFLW Match Highlights: Greater Western Sydney v Melbourne

The Giants and Demons clash in a semi-final of the AFLW

A wasteful GWS was left heartbroken by Mithen's second goal as the Demons got home 4.5 (29) to 3.8 (26).

Incredibly, Mithen went into the semi-final without an AFLW goal to her credit.

The Giants went into their maiden final as underdogs against the more experienced Demons, but in a low-scoring affair played in perfect conditions in Sydney, the home side looked to have broken the game open in the third term.

DEMONS HOLD ON Full match coverage and stats

It booted the only two goals of the quarter while keeping Melbourne scoreless.

However, the Demons' experienced brigade shone through after the last change when the game looked lost, with Karen Paxman (20 disposals) outstanding through the midfield, Daisy Pearce (22) and Libby Birch (15) strong across half-back, and Lauren Pearce (14 and 13 hitouts) in control in the ruck.

00:43

Mithen's second seals stunning Dees comeback

Lily Mithen's second career goal sends Melbourne into a preliminary final

Veteran Shelley Scott and the enigmatic Sarah Perkins, who had hardly been sighted throughout the clash, kicked Melbourne's other two goals in the last quarter with clutch set shots.

Star GWS midfielder Alyce Parker was the most influential player on the ground and finished the day with a game-high 23 possessions, with fellow onballers Bec Beeson and Britt Tully also good.

00:30

Cora comes through with the goods

A crafty goal from Cora Staunton extends the Giants' lead

Jess Dal Pos, Tanya Hetherington and Elle Bennetts were tireless and resolute in defence for the Giants and did a power of work, while Haneen Zreika and Rebecca Privitelli were lively forwards.

Melbourne's stunning victory will give them plenty of confidence next week, but the devastating loss will be tough for the Giants to live with in the off-season.

The first blow

Both teams struggled to find an opener despite plenty of opportunities close to goal, and it took until almost five minutes in the second term for the Demons to get on the board. Mithen received a questionable free kick for high contact in the right forward pocket and calmly went back and slotted it from a tight angle.

00:24

A four-year wait for loyal Dee's first-ever goal

Lily Mithen scores her first career goal after four seasons

The moment

Melbourne dominated the second quarter but couldn't capitalise on the scoreboard, and the Giants took full advantage. After she'd missed an easy chance minutes earlier, Aimee Schmidt picked up a loose ball and without much of a look, snapped a brilliant goal to cut the margin to one point 30 seconds before half-time.

00:25

Aimee's aim true as Giants fight back

Aimee Schmidt with a skilful snap in the shadows of half-time

The hero

Mithen took a strong mark inside 50 opposed to the more experienced Annalyse Lister, who won't want to watch the replay of her one-on-one effort in the contest. As the clock ticked down to full-time, the exciting Demon handled the biggest moment of her career with ease. 

The difference

The difference in experience between the two sides was evident in the last term when the Demons roared back into the contest. The Giants had opportunities to slow the game down at various stages or keep possession with control of the footy but couldn't hold their nerve. It will be a great learning experience for the young side.

It was over when…

The Giants had one last shot at it when Bennetts grabbed the footy in the centre square and pumped it forward, but her kick was a shank and went straight to the Demons. The visitors held on in the frantic finals seconds to pull off an amazing win.

Say what?

"To go into that last quarter with nothing to lose and see it come off was pretty special." - Melbourne captain Daisy Pearce

"We're shattered. We'll take a lot out of the season, but by no means are we happy. You play footy to win premierships and this will drive us that’s for sure."  - GWS captain Alicia Eva

What’s next?

The thrilling win keeps the season alive for Melbourne, who will play the winner of Fremantle and Gold Coast, while for GWS an encouraging 2020 season is over.

GREATER WESTERN SYDNEY    0.2    1.4    3.7    3.8 (26)
MELBOURNE                                0.1    1.5    1.5    4.5 (29)

GOALS
GWS: Schmidt, Staunton, Dal Pos
Melbourne: Mithen 2, Scott, Perkins

BEST
GWS: Parker, Bennetts, Beeson, Zreika, Hetherington, Tully
Melbourne: Paxman, Birch, D.Pearce, Mithen, L.Pearce, Zanka

INJURIES
GWS: Nil
Melbourne: Nil

Reports: Nil