Chile star Arturo Vidal gave his team a timely boost just two days before their opening FIFA World Cup™ clash against Australia by training with his team-mates.

The 28-year-old midfielder has been struggling with inflammation in his knee following an operation on his meniscus just over a month ago. But the Juventus dead-ball specialist trained with his team-mates on Wednesday, the first time he has been able to do so since making a surprise 15-minute cameo comeback a week ago in the 2-0 friendly victory over Northern Ireland.

Vidal joined the squad a few minutes after they had come out to train at their Toca Da Raposa II base in Belo Horizonte, and showed no signs of discomfort. Until Wednesday, Vidal had been training alone, undergoing physiotherapy and doing specific exercises to improve the condition of his knee.

I believe Chile will win the World Cup, if I didn't believe that I would be sitting at home in front of the television.

Chile forward Alexis Sanchez

However, in the 15 minutes that were open to the press, Vidal clearly was not in full training, nor striking the ball with any power, although he was kicking again with both feet. Vidal is a vital cog in coach Jorge Sampaoli's team and his presence will be imperative in their next two games against Spain and the Netherlands if they want to progress to the knock-out stages.

Despite being drawn in such a tough group, forward Alexis Sanchez is feeling confident about their chances, although he acknowledges it will be hard to finish above reigning champions Spain in Group B.

"I believe Chile will win the World Cup, if I didn't believe that I would be sitting at home in front of the television," he told Brazilian newspaper O Globo.

"I would be happy if we finished second behind them (Spain)."