Victory skipper's mystery illness

Victory great Archie Thompson could play a part in next week's Melbourne Derby but in bad news for the Hyundai A-League champions, captain Carl Valeri has been diagnosed with a illness affecting his balance.

Victory coach Kevin Muscat revealed on Friday that Valeri is out indefinitely, with the reigning A-League champions waiting on the results of tests to ascertain the skipper's situation.

Valeri was a late withdrawal from Victory's squad that travelled to New Zealand last week after he picked up a virus, but it appears the 31-year-old's condition has worsened.

"It's just not good news for Carl, unfortunately," Muscat told reporters on Friday. 

"He was diagnosed with a virus about 10-12 days ago. That's now developed into some sort of condition that's affecting his balance.

"So he's undergone quite a bit of testing in the last few days, with some more testing [set for] early next week and, at this point in time, it's obviously a matter we're taking very seriously."

Valeri has missed three of Victory's past four matches due to a combination of suspension, hamstring issues and this illness.

Kevin Muscat presents the Westfield FFA Cup trophy to Carl Valeri.

When asked about his captain's head-space, Muscat responded: "Naturally, it's not great. First and foremost, his wellbeing is paramount."

But in some better news for the A-League title-holders, Muscat dismissed rumours Thompson's career could be over and even hinted at a Derby comeback for the veteran striker.

Thompson has been sidelined since the Westfield FFA Cup quarter-finals with a knee injury, and after he ended training early on Wednesday, speculation flourished that the 37-year-old may never recover.

"He didn't limp off with injury, anyway," Muscat argued.

"He didn't finish the training session but he wasn't injured. He trained very well this morning again; he's edging nearer and nearer to being involved again."

Archie Thompson on the training ground.

While it is hard to imagine Thompson could be fit to play again so soon after damaging his medial ligament in September, Muscat hinted Victory's all-time leading goal-scorer could play next week against Melbourne City.

"We'll get through another week's training next week but I wouldn't rule it out," the Big V's coach said.

Victory will head north tomorrow to play Western Sydney Wanderers in a top-of-the-table clash and after their disappointing 2-0 loss away to Wellington Phoenix last week, Muscat made it clear his team is keen to produce their best football in front of a packed Pirtek Stadium.

Hyundai A-League preview: Wanderers v Victory

"It's going to be a contrasting game of football to last week. But we've got back, obviously licked our wounds all week, and look forward to going across there and putting on a good show and good performance," he said.