Sikora had an eventful start to last Sunday's loss in Wellington, injuring his quad during the opening minute when caught in a tough Michael Ferrante tackle.

Down but not out, Sikora got his own back on Ferrante when he picked the defender's pockets three minutes later to open the scoring for Perth. But the Dutchman was forced off before the half hour and looks unlikely to play in the club's first home game this season.

"There's a good chance Victor probably won't play but we'll wait and see 'til later in the week," Glory coach Dave Mitchell said after training.

"He's had scans and the scans have said there's a bit of inflammation there and a bit of swelling, but there's no tear, which is positive.

"(But) it's 50-50 at the minute and it's just as each day goes on, whether that (inflammation) goes down in time."

Sikora was one of two enforced early substitutions for Glory, coming off just two minutes after Australian international Chris Coyne left the field with a stomach virus, from which he's now recovered.

The early changes forced Mitchell to re-shape the team, throwing midfielder Adriano Pellegrino into a defensive role at right back, youngster Scott Neville into centre-half and former WA State League player Todd Howarth into the left midfield role vacated by Sikora.

In a dramatic 15-minute period, unsettled Glory looked all at sea as Phoenix attacked with intent. But after half-time, the visitors dominated proceedings and attacked Wellington's goal at will before being stunned by a 35-metre Leo Bertos thunderbolt that claimed the points with five minutes remaining.

Howarth, though, was at the heart of many forward runs for Glory with his intelligent crosses in the wet and windy conditions setting up numerous chances, and his curling ball to Mile Sterjovski in the 58th minute unfortunately headed against the crossbar.

Having seen Howarth step up after a lacklustre debut against Adelaide, Mitchell said there's a good possibility the 25-year-old could start on the left against Newcastle this weekend.

"With Todd, we threw him in the deep end against Adelaide and he played in a central role (where) he didn't do the best and he was criticised by a lot of people," Mitchell said.

"To go out with that performance when he came on was fantastic for the kid and it just shows you that he has got quality.

"It's opened up a lot of people's eyes to think that someone from the State League, who's a good player, can make it in the A-League if they're prepared to be determined and make sacrifices."

With normal right midfielder Pellegrino forced into defence, Mitchell used star signing Sterjovski in that position and hinted he may do it again this week after the Socceroo looked more dangerous there than as an outright striker.

"We're going to try him in a few different roles, not only him but a couple of other players," Mitchell said. "We might play differently this week or we might not."

One player not available for selection this weekend is Brazilian midfielder Amaral. The 2002 World Cup winner has trained with Perth for the last week. Mitchell said a decision on whether he's granted a nine-match guest position in the squad will be made next week.