The Giants led for most of the game, apart from a short period in the third quarter, on their way to a 10.19 (79) to 7.5 (47) victory at Spotless Stadium.

Leading by just one point early in the final quarter, GWS slammed on four straight goals - two to midfield rookie Josh Kelly and one each to ruckman Shane Mumford and small forward Devon Smith.

''The good thing about the game is that, when Melbourne came at us at the back-end of the third quarter, for them to get in front and us to respond, I thought was fantastic and helped us in playing a dominant last quarter,'' coach Leon Cameron said.

''Our fitness staff, our sports science area, has done a great job over our pre-season. It gives you great confidence that when you come to that three-quarter-time siren, we break and then know we've got the run in the legs to last the last quarter.''

The result improved the Giants' record to 2-1 and left Demons coach Paul Roos still looking for his first victory.

Melbourne became the first team to lose twice to the Giants, who have already equalled their previous best season win tally of two.

Kelly and key forwards Jeremy Cameron and Jonathon Patton each kicked two goals, while Jack Watts and Lynden Dunn both booted two goals for the Demons.

The Giants led 33-17 during the second quarter, but three straight goals to Melbourne briefly gave it the lead in the third term.

GWS hit back to lead by seven at the last change, only for a James Frawley goal to cut the deficit to a point. Midfielder Adam Treloar revelled in the wet, piling up 33 possessions and laying 14 tackles.

The Giants finished 79-37 ahead in hitouts, with Mumford tallying 60.

What the match - watched by a crowd of just 7016 - lacked in skills and execution in challenging, drizzly conditions, atoned with a result that remained in doubt until the Giants repeated the type of big last-quarter push that gave them victory against the Swans in round one.

In the context of what had been a low-scoring scrap for most of the afternoon, it was a final-quarter deluge, the Giants kicking five goals.

With nothing to lose after last week's 93-point loss to West Coast, Roos restructured his Demons, putting Frawley and Dunn in the forward line.

Yet, as had been the case in previous rounds, the Demons failed to turn possession into goals due to poor disposal. After Cameron's snap put GWS ahead, the Demons showed application but had only two behinds to show for it.

In the second quarter the Giants won nearly double the clearances, had made 21 more tackles and Mumford won more than double the hitouts, but they had only one goal for the term, from Patton.

Dunn's mark and goal for Melbourne nearing half-time left the deficit eight points.

GWS gained eight inside-50s in the first 16 minutes of the second half, leading to two goals.

But Melbourne hit back with majors to Watts and Dean Kent as the game began to open up.

The Demons made it an 18-point spree with Dunn's second, putting them ahead for the first time, but Cameron's snap gave GWS the upper hand entering the final quarter.

Frawley's goal put the Demons within a point early in the last quarter.

But that was the spark the Giants needed and they piled on the pressure to gain their second win from their opening three games.

With aap