Perth Glory coach Dave Mitchell could be forced into some last-minute adjustments to his side for Sunday's clash with Queensland as Nick Rizzo faces a battle against time to be fit.
The skillful left winger appeared to be struggling with a groin injury during training on Friday, with Mitchell admitting Rizzo's absence might mean some tinkering with side's structure.
The injury couldn't have come at a worse time for 29-year-old Rizzo as the former Liverpool and Crystal Palace player had started in the last two matches and appeared to be consolidating his position in the side following a bad run with injuries.
"He (Rizzo) looks like he could be out," admitted Mitchell on Friday.
"But we just got to re-adjust and see what we're going to do now, who can replace him and what formation we're gong to go with."
With former Socceroos defender Hayden Foxe (leg, three weeks) and Brazilian midfielder Amaral (knee, one week) also unavailable, Mitchell suggested Rizzo's absence could force him to bring defender David Tarka back into the side quicker than expected.
Earlier in the week Tarka declared himself fit to go after recovering from a nerve-related quadriceps injury. But the towering defender said he would probably need to gain match fitness through the Glory's National Youth League side.
If Tarka was fast-tracked into the side, though, he would probably return to his regular centre back position alongside Dino Djulbic, pushing Nikolai Topor-Stanley into left back where he struggled earlier this season. Regular left-back Naum Sekulovski would then be pushed further up the ground to replace Rizzo on the left side of midfield.
Rizzo's absence could therefore mean wholesale changes to a defensive structure that's been relatively successful over the last four matches as the Glory's only conceded five goals, winning twice and suffering an unlucky loss to Adelaide, along with a last-gasp 2-2 draw with Newcastle in round 11.
Mitchell, though, also has the luxury of using club veteran Jamie Harnwell in his backline as he attempts find a way to shore up his defence, which now might be vulnerable to Queensland's counter-attacking style and to Charlie Miller's craftiness in the forward third.
But the coach was keeping his cards close to his chest in regard to what formation he might adopt.
"Look I think we've got a bit of depth and that's going to be tested to the full now," Mitchell said.
"But the boys that are coming in, we'll have a look and see, (for) the next month is so crucial."
"We're (also) looking forward to next season as well with recruiting and players, so it's a chance for the players who haven't probably been playing to see if they take it or not."
Mitchell also said Craig Moore's cancer diagnosis was extremely sad for the Queensland club, but said his players must take advantage of Moore's possible absence - there are whispers the Roar skipper could be a shock last-minute addition to the side - in order to claim the Glory's first away win of the season and its first victory over the Roar since round three 2005/06.