Injury-hit Australia [Images] must decide whether to gamble on the fitness of Mark Viduka when they play for their Confederations Cup future with Group A favourites Argentina in Nuremberg on Saturday.

Australia coach Frank Farina opted to play John Aloisi as a lone striker in Wednesday's unlucky 4-3 defeat by hosts Germany [Images] and the Osasusna forward responded with two well-taken goals.

Viduka, itching to make a comeback after six months of injury problems, was left on the bench but Farina is likely to call on his top striker as Australia bid for the win they need to stand a chance of making the semi-finals.

"Mark is keen to play and he's looking good in training but we weren't sure about him for that intense first match," Farina said.

"We'll give him the extra training sessions before the next game and possibly use him off the bench."

Farina will definitely have to find a replacement for defender Tony Popovic, who could be out for the rest of the tournament after suffering an ankle injury against Germany. John McKain should be the man to come in. Argentina were in control against Tunisia for all but the opening few minutes of their impressive 2-1 win and Farina is under no illusions about the difficulty of the task facing his side.

"Argentina are one of the best teams in the world, if not the best," he said. "It will be a tough ask but if we play like we did against Germany we have a chance."

TUNISIA BOOSTED

Tunisia's French coach Roger Lemerre will have the option of strengthening his team throughout for their clash with the hosts in Saturday's first match.

Tunisia lined up without six regulars against Argentina, including forwards Ziad Jaziri and Santos, and they promise to pack a heftier punch in the second game.

"We're a small team but little mosquitoes can still sting large animals," Lemerre warned.

Germany know they were lucky to escape with a win against Australia after their comical defending and captain Michael Ballack [Images] is demanding an improved performance.

"If we keep conceding what are effectively own-goals we're going to continue having problems," said Ballack.

Per Mertesacker, who blasted in Germany's second goal, should recover from a slight knock to play but Juergen Klinsmann is due to make at least one change, with Jens Lehmann coming in to replace Oliver Kahn in goal as part of his rotation policy.

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