Brazil forward Ronaldinho [Images] has been told by his national coach Dunga to improve his fitness levels if he wants to regain the mantle of the world's best player.

"Kaka [Images] is the best player at the moment, Ronaldinho has the capability to return to the top and Robinho could be up there," Dunga was quoted as telling Catalunya Radio in the Spanish media on Monday.

"Ronaldinho lacks pace at present. He lacks that initial burst of speed that allows him to get away from rivals."

The 27-year-old Barcelona player has been criticised by fans and the Spanish media for being overweight, out of shape and missing training sessions during the Primera Liga season.

Although he has been inconsistent, he is the side's top scorer with 20 goals.

"He has to train more. A Ronaldinho at peak fitness is impossible to stop as seen last year. Technically he is better than the rest," Dunga added.

Ronaldinho has asked to be left out of Brazil's squad for the Copa America starting later this month, to be able to rest and prepare for next season without interruption.

Barca are level on points with leaders Real Madrid in the league, but second due to their inferior head-to-head record with two games left.

Ronaldinho is suspended for Barca's home game against Espanyol on Saturday after being sent off against Getafe, and will be able return for the final game of the season against relegated side Gimnastic Tarragona.

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