Fringe Socceroo Craig Goodwin looks unlikely to feature for Adelaide in next weekend's A-League semi-final against Sydney FC.

The Reds defeated Brisbane 2-1 on Sunday at Moreton Daily Stadium in their elimination final without Goodwin after the winger suffered an ankle injury in training on Saturday.

While the 29-year-old has been cleared of a fracture, coach Carl Veart fears the injury is "fairly serious".

"He'll have a scan on Tuesday," Veart said.

"He's had an X-ray, there's no break there but the way he went down, the pain he was in, it didn't look good.

"We can keep our fingers crossed and hopefully it's not too bad but he was in a lot of pain so I think it will be fairly serious."

Goodwin has been sensational since returning to Adelaide in February on loan from Saudi Arabian club Al-Wehda, scoring eight goals in 18 appearances.

While the Reds secured a first away finals win in club history without him on Sunday against the Roar, Veart admitted the challenge gets even harder for his club in next Saturday's game with Sydney FC at Netstrata Jubilee Stadium.

A rested Sydney are chasing an unprecedented third-straight championship and Veart said it was obvious his team would be underdogs.

"Of course we have," he said when asked if his team have anything to fear.

"They showed that to us about three or four weeks ago when they gave us a bit of a beating at home.

"They've got some quality, quality players ... they don't need many opportunities and they hurt you.

"We have to be focused and make sure we don't give their quality players too many opportunities."