Momentum is a dangerous weapon in football.

And after a 2-0 start to the season, the Saints will head west with a full head of steam, determined to continue their unbeaten streak.

It was only a fortnight ago when Ross Lyon’s Dockers put North Melbourne to the sword, burying the Kangaroos with manic speed, repeat entries and heavy scoring.

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But last week against Gold Coast, Freo’s free-flowing football was put on hold, going down by three points against the spirited Suns.

Sunday will mark just the Saints’ second clash against the Dockers at Optus Stadium, their first outing at the Freo fortress resulting in a 30-point loss.

While the Saints managed to turn the tables in the second half, Fremantle’s class – led ably by skipper Nat Fyfe – was too strong.

Fyfe is back to his brilliant best in 2019, putting in two consecutive 30+ disposal efforts and a total of 19 clearances.

His last encounter with the Saints was just as damaging, as he finished with 36 possessions (25 contested) 13 clearances and a goal to boot.

And it will likely be up to Saints enforcer Jack Steele to curtail the Brownlow medallist.

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The 23-year-old caught the eye of the competition for his impressive shutdown roles in the back half of 2018, and he’ll hope to add Fyfe to his growing list of scalps.

Leading the entire league for tackles (17), Steele’s physicality around the contest and damaging two-way run will cause headaches for the Dockers.

While it’s easy to highlight Fyfe as Fremantle’s sole contributor, the speed of Ed Langdon, Bradley Hill and Andrew Brayshaw could prove just as crucial.

St Kilda will be without one of their own key runners in Jack Steven, who has been managed after an interrupted pre-season.

Former Giant Cam McCarthy has been influential, booting seven goals in the past two matches.

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With Rory Lobb floating through the forward line and Jesse Hogan in the mix after piecing together a 21-disposal effort in his debut in purple, the Fremantle forward line poses a significant threat.

Fremantle have averaged 67.5 inside-50s from their first two matches, up from their average of 48 in Season 2018.

Off the back of St Kilda’s pressure-laden effort against the Bulldogs – spearheaded by Jack Sinclair, Jack Lonie and Rowan Marshall – the Fremantle defence will be under siege, with the rejuvenated Alex Pearce and Joel Hamling integral in stifling the Saints.

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Fremantle are on the rebound and keen to bounce back.

St Kilda are gunning for an unbeaten 3-0 start to the year.

An imposing fortress, a star-studded side and a sea of purple stand in their way, but the Saints are up for the fight.