After three consecutive league wins, the defending champions (39) are one-point clear of last season's grand finalists the Western Sydney Wanderers (38) with two home-and-away fixtures remaining.
In that period, the Mariners have claimed victories over the Newcastle Jets, Melbourne Heart and Western Sydney, while they also stunned Chinese giants Beijing Guoan in midweek AFC Asian Champions League action.
Phil Moss' men, who have continued to defy the odds this season, head to nib Stadium full of confidence against a team, who have only won one of their past 11 games to languish at the foot of the table.
Central Coast will also take heart from the fact that they have already beaten Perth twice this season, though the Mariners have since lost Trent Sainsbury (PEC Zwolle), Michael McGlinchey (Vegalta Sendai) and Daniel McBreen (Shanghai SIPG).
If the Mariners fail to secure maximum points from their trip to Western Australia, it will open the door for Western Sydney, Adelaide United (37) and Melbourne Victory (37), who are all chasing that coveted second spot.
Western Sydney, who went down 2-1 to Kawasaki Frontale in Japan in the Asian Champions League midweek, host Premier's Plate winners the Brisbane Roar at Pirtek Stadium on Saturday.
Wanderers coach Tony Popovic is expected to rotate his squad once again as his side battle for top honours domestically, and in Asia.
A Western Sydney loss, combined with a Central Coast victory, would see Moss' side seal the all-important second spot ahead of the finals.
As for Adelaide, touted as a dark horse for the title, they play host to struggling Melbourne Heart at Coopers Stadium on Friday.
A total of 12 points separates Adelaide and Heart in the table, though the two previous fixtures this season ended all square.
Melbourne Victory will face a test of their depth when they go head-to-head with finals hopefuls the Newcastle Jets at Hunter Stadium on Saturday.
After just two days' rest following their trip to Japan on Wednesday, Victory must regroup to tackle a Jets outfit (32), who are one-point shy of Sydney FC (33) in the race for a top-six finish.
The Sky Blues earned a draw against Victory last time out but remain winless in three games ahead of Sunday's clash against Wellington Phoenix at Allianz Stadium.
