``We've seen his performances drop but there's no reason to be worried,'' Rijkaard told Catalan radio station RAC 1 late Wednesday. ``We're dealing with it. He's doing what he can for the team and that's enough because he works for the team.''

The coach attributed Ronaldinho's slump to a lack of rest following the World Cup. He said the 26-year-old Brazilian forward had to play in all Barcelona's pre-season games due to contractual obligations.

``He is a key player but he isn't a machine or a robot. Sometimes we forget he is a human being,'' he said.

Rijkaard said Ronaldinho had got over his disappointment at Brazil's poor showing in Germany. The five-time champion lost to France in the quarter-finals.

``What happened to him at the World Cup isn't going to affect Ronaldinho any more. He showed a good attitude but his team couldn't connect with him. That's the only thing which makes the difference between playing well or brilliantly,'' Rijkaard said.

The Brazilian echoed his coach's sentiments in an interview with daily El Periodico, published Thursday.

``I'm not worried. Why should I be?'' he said. ``I feel comfortable and I'm working to help the team. That's my aim. When the team needs me, I'll be there.''

Ronaldinho, the FIFA world player of the last two years, has scored twice in his opening six league and Champions League games, although this is not his worst start with Barcelona. In each of his first two seasons since he arrived from Paris Saint-Germain in 2003, he had only managed a single goal at the same stage.

Despite Ronaldinho's difficulties, Barcelona heads the Spanish league with 13 points from five games _ its best position at this stage of the season since Rijkaard took charge in 2003. The team lies second in Champions League Group A.