JOSH Kelly has kicked a monster winning goal to snatch Greater Western Sydney a dramatic two-point upset win over a wasteful Melbourne and thrust GWS into the finals-chasing pack.

The Giants appeared destined to fall short with about two minutes left in the final quarter in Alice Springs when Kelly marked, played on and launched from close to 60m out.

GWS held on for a dramatic 7.5 (47) to 5.15 (45) victory that puts the Giants four points outside the eight and leaves the Demons' top-four spot vulnerable.

DEMONS v GIANTS Full match coverage and stats

The loss, Melbourne's second on the bounce, leaves the fourth-placed Demons (36 points) eight points behind third-placed Brisbane and only ahead of the fifth-placed Western Bulldogs on percentage.

The Demons also lost gun forward Bayley Fritsch to a first-quarter foot injury.

Fritsch was caught in a big pack of players when flying for a mark and appeared to have his foot stepped on.

He immediately left the field for assessment and was substituted for Jake Melksham.

Unsurprisingly, Melbourne and GWS midfield bulls Jack Viney and Tom Green both got to work in the wet and won plenty of contested ball respectively.

Viney racked up 40 disposals, eight clearances and 607 metres gained and was well-supported by a wasteful Christian Petracca (34 disposals, 556 metres gained), while Angus Brayshaw and Steven May were important.

Green (38 disposals, 16 contested possessions), Kelly (26) and Stephen Coniglio (30) had plenty of the footy for the Giants.

Melksham booted the Demons' first goal as they endured a wasteful start in difficult conditions, struggling with the Giants' relentless pressure.

Petracca kicked four behinds in the opening half while Toby Greene booted two second-quarter goals to keep the Giants in the thick of things, with scores level at half-time.

The Giants came out of the main break with greater intensity and it soon paid off.

Xavier O'Halloran put GWS in front with a close-range free kick and Josh Kelly snapped another shortly after.

Isaac Cumming nudged the Giants out to an 18-point lead midway through the third quarter.

But Brodie Grundy and Kysaiah Pickett responded to tighten up the contest.

Ed Langdon kicked a terrific set shot early in the fourth quarter to put the Demons back in front.

The Giants attacked time after time without reward, until Kelly let loose with the decisive long bomb.

Where's the Alice sunshine?
It seems the Melbourne weather followed the Demons on their trip to the Red Centre. While Alice Springs averages a lovely 20 degrees at this time of year, it was far from it on Sunday as the Demons and Giants faced off in rain, fog and at times, strong winds as temperatures hovered around an uncharacteristic eight degrees. The slippery conditions led to poor disposal from both teams, with Melbourne kicking at just 62.5 per cent efficiency, while the Giants went at 66.2 per cent efficiency, well below their season averages.

Briggs a ruck on the rise
Young GWS ruckman Kieran Briggs had a giant job in front of him, coming up against star big men Max Gawn and Brodie Grundy – who boast a combined eight All-Australians between them. But rather than shirking the job at hand, Briggs stood up to the challenge and showed why he is a ruck on the rise. The 23-year-old finished with an equal game-high 19 hitouts, five clearances and six tackles.

No Fritsch, no worries as super sub impacts early
Lively Demons forward Bayley Fritsch was subbed off just seven minutes into the opening quarter after injuring his foot in a marking contest in the forward 50. But it didn't take long for his replacement, Jake Melksham, to have an impact, kicking a goal immediately – the Demons' first of the day. It took Melbourne 17 inside 50's before the 31-year-old was finally able to break through for his side's first major.

MELBOURNE                             1.5    2.9     4.12    5.15 (45)
GREATER WESTERN SYDNEY   1.0    3.3     6.4      7.5 (47)

GOALS
Melbourne: Bowey, Grundy, Langdon, Melksham, Pickett
Greater Western Sydney: Greene 2, Kelly 2, Brown, Cumming, O'Halloran

BEST
Melbourne: Viney, Hunter, Petracca, May Bowey, Pickett
Greater Western Sydney: Coniglio, Green, Kelly, Greene, , Briggs, Himmelberg

INJURIES
Melbourne: Fritsch (foot)
Greater Western Sydney: Nil

SUBSTITUTES
Melbourne: Jake Melksham (replaced at Bayley Fritsch in the first quarter)
Greater Western Sydney: Ryan Angwin (replaced Daniel Lloyd in the fourth quarter)

Crowd: 3,413 at TIO Traeger Park