JOSH Kelly has kicked a monster winning goal to snatch Greater Western Sydney a dramatic two-point upset win over 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.

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.

Jack Viney was prolific in the match, racking up 40 disposals and 24 contested possessions as he did his best to will the Demons over the line.

00:50

RD 16 | Dees catch fire with two in hot minute

Goals to Brodie Grundy and Kysaiah Pickett in quick succession brings Melbourne to within a straight kick

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.

00:38

RD 16 | Bowey snaps Dees back in front

Jake Bowey rewards his side's forward pressure with this snapping goal early in the second quarter

The best-afield Viney was well-supported by a 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.

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: TBC at TIO Traeger Park