AAP


Perth Glory's disastrous weekend on the injury front could prove to be a major boost for the finals chances of A-League rivals Brisbane, Sydney and Newcastle.


The Glory sit in seventh spot, but will finish fifth or sixth if they defeat Adelaide United at nib Stadium on Saturday.


However, the injury curse has struck Perth at the worst possible time, with four key players set to miss the crunch clash.


Midfielder Travis Dodd is facing a lengthy stint on the sidelines after tearing the anterior cruciate ligament in his left knee during Saturday's 3-2 win over Melbourne Victory.


Winger Chris Harold (calf) and playmaker Liam Miller (suspended) will also definitely be absent, while banged-up striker Shane Smeltz is considered extremely unlikely to play.


Smeltz required 15 stitches to his face after copping an errant boot while playing for New Zealand last week.


It was a scene reminiscent of last year's grand final, when Smeltz needed plastic surgery after copping a stray elbow to his face.


The 31-year-old has opted against undergoing another round of plastic surgery, but won't return to Perth until Thursday night.


Brisbane and Sydney are clinging to fifth and sixth spots respectively.


But given they play each other on Thursday night, they are in danger of being overhauled by Perth or Newcastle, who sit just one point further behind.


If ladder-leading Western Sydney beat Newcastle on Friday night and a depleted Perth lose to Adelaide, then Brisbane and Sydney are guaranteed spots in the finals.


The Wanderers need just a draw against Newcastle to secure the Premiers' Plate, but will have to achieve the feat without key utility Iacopo La Rocca.


La Rocca has accepted a four-match ban for crudely elbowing Sydney FC's Terry Antonis, meaning he will miss the grand final even if the Wanderers make it that far.


The 29-year-old's absence is a major concern for coach Tony Popovic, who is also sweating on the fitness of Japanese star Shinji Ono, Jerome Polenz, Michael Beauchamp and Aaron Mooy.


Dodd, who has played a key role for Perth this season, will consider undergoing a LARS procedure to speed up his recovery.


Harold is also unlikely to play again this season after being ruled out for up to four weeks with a torn calf.


But in some better news, Glory will be boosted by the return of skipper Jacob Burns from suspension and Socceroos defender Michael Thwaite from international duty.