Five-goal hauls from Lance Franklin and Tom Papley have helped an undermanned Sydney record its most impressive win of the season, a 45-point victory over West Coast at the SCG.

Franklin (5.4) and Papley (5.2) led the way on Sunday as the Swans started strongly and answered every challenge from the reigning premiers, prevailing 18.8 (116) to 10.11 (71).

Injured backmen Jarrad McVeigh (suspected left quad), Colin O'Riordan (concussion) and Jackson Thurlow (head) all played no part in the second half.

Despite being down to one fit man on the bench, John Longmire's team dug deep to make co-captain Dane Rampe's 150th game one to remember.

Rampe, Jake Lloyd, Callum Mills, Luke Parker, George Hewett and Isaac Heeney all played key roles in Sydney's fourth win for 2019, which attracted 36,640 fans.

Franklin enjoyed his most productive outing of the season, as did the Swans, while Sam Reid booted three goals to extend the Eagles' miserable streak at the SCG.

West Coast, squandering a golden chance to claim second spot on the ladder, have lost nine straight games at the venue in a horror stretch dating back to 1999.

The visitors, who sorely missed injured captain Shannon Hurn and two-time club champion Elliot Yeo, reduced the margin to 19 points early in the third term but it was the closest they came to hitting the front after half-time.

Franklin, who underwent off-season groin surgery and missed rounds 6-9 because of a hamstring injury, set the tone when he booted Sunday's opening goal after marking on the lead.

The 32-year-old, featuring in his 298th match, repeated the dose in the second term when he broke free from Jeremy McGovern and slotted the subsequent set shot from beyond the 50m arc.

The superstar's fourth goal was textbook Buddy, coming after benefiting from Daniel Menzel's pinpoint pass and buffeting would-be tackler Tom Cole with apparent ease.

Franklin also twice dished off goals to Papley.

Intercept king McGovern and Will Schofield each spent time on Franklin but neither was able to shut down the four-time Coleman medallist.

At the other end of the ground, Eagle Josh Kennedy's duel with milestone man Rampe was also engaging viewing.

Kennedy finished with three goals, having notably stood up when the Swans threatened to run away in the first term, but Rampe kept him goalless after half-time.

Both teams have the bye in round 13 but West Coast forward Willie Rioli might spend another week on the sidelines, having knocked out O'Riordan with a sling tackle in the second quarter.

SYDNEY                       4.1       9.6       14.7     18.8 (116)
WEST COAST              3.2       6.3       7.8       10.11 (71)

GOALS
Sydney: Papley 5, Franklin 5, Reid 3, McCartin, Rose, Hewett, Sinclair, Parker
West Coast: Kennedy 3, Ryan 2, Rioli 2, McGovern, Darling, Waterman

BEST 
Sydney: Papley, Franklin, Parker, Hewett, Reid, Heeney
West Coast: Shuey, Kennedy, Ryan, Sheed, Redden

INJURIES 
Sydney: O'Riordan (concussion), Thurlow (head), McVeigh (left thigh)
West Coast: Nil

Reports: Nil

Umpires: Margetts, Hay, Meredith, Fleer

Official crowd: 36,640 at the SCG