Ronaldinho in Abramovich's sights after agent meeting

Chelsea were yesterday drawn into potentially one of the most controversial transfer sagas of the summer as well as the politics of Ronaldinho's attempts to negotiate a new contract with Barcelona. Reports of a meeting between the Brazilian international's brother and Roman Abramovich, Chelsea's owner, provoked an angry response from Barcelona that they were not about to sell their most famous player.

The Spanish club believe that leaked stories of a meeting between Ronaldinho's brother and agent, Roberto de Assis Moreira, and Abramovich are designed to put pressure on them to improve the 27-year-old's pay-deal. It is a tactic with which they are familiar following Ronaldinho's dalliances with Milan in recent years, but this time they intend to be more militant after a poor season by his standards.

Abramovich was reported to have had two meetings with Moreira over the weekend, which Chelsea would not confirm. What is not in doubt was that Ronaldinho's brother was in London and attended Arsenal's match against Manchester City on Saturday in one of the Emirates stadium's executive boxes. Abramovich is known to work independently of his club's hierarchy at times and it is understood that the manager, Jose Mourinho, and chief executive, Peter Kenyon, had not been made aware of any potential move for Ronaldinho.

Barcelona's sporting director, Txiki Beguiristain, said the club would not entertain the prospect of selling their most famous player. "We do not want to sell him," he said. "Ronaldinho is our player and I am totally convinced that he will remain at the club." Bringing together the various strands of a potentially labyrinthine

deal in time for Friday's transfer deadline would seem to be beyond even Abramovich's influence.

In Barcelona, the club believe that the story, which originated in the Spanish press, came from the player's camp. Ronaldinho has been given a pay rise every year since he signed in 2003, often on the basis of interest from other leading European clubs.

However, after last season, in which Barcelona lost their Spanish and Champions League titles, the club have been less willing to listen to Ronaldinho's demands. Talks over a new deal, to extend his current contract from 2010 to 2014, broke down last season and were not expected to be revived until much later this year.

It was there that Chelsea entered the narrative and Abramovich's reported personal intervention will clearly have an effect on the Barcelona hierarchy. The Russian is known to want Chelsea to play a more attractive style of football and Ronaldinho would clearly be suited to that ambition. But even Chelsea's highest officials were none the wiser yesterday as to whether Abramovich had made an offer to Moreira – or even if there is a viable deal to be done with Barcelona and Ronaldinho.

Ronaldinho was granted dual nationality this week and is now a Spanish citizen. Having taken the oath of allegiance to the Spanish constitution he is no longer counted as a non-EU player, of which Spanish football regulations permit only four in every team. His advisers believe that also makes him a more valuable asset to his club and that his pay should change accordingly.

Armed with that, and potential interest from Abramovich, his advisers clearly have a stronger case with which to negotiate despite Ronaldinho's stock falling last season. Twice named Fifa world player of the year, his fondness for a night out appeared to have an impact on his performances and while he never admitted as much publicly he did concede in interviews that his physical condition was not as good as it had been.

Completing a deal for Ronaldinho would be fraught with complexity, as Kenyon found out when he tried and failed to sign the player for Manchester United in the summer of 2003. Over the past few seasons, Moreira has done deals in which Ronaldinho has given up shares in his image rights in return for a bigger salary package. Agreeing a transfer fee and personal terms now with Chelsea would be a huge undertaking.

Even though Chelsea now lead the Premier League table, there are several issues still unresolved at Stamford Bridge quite apart from whether their Russian owner is about to pull off one of the most stunning transfer coups in recent football history. Chief among their concerns is the fitness of Michael Ballack, who still feels pain in his ankle that was injured by a Titus Bramble challenge on 22 April. He does not have a date to return to action.

The future of Andrei Shevchenko is once more in doubt after he played and scored for Ukraine in their 2-1 win over Uzbekistan on Wednesday but did not feature in the Chelsea squad that played Portsmouth at the weekend. So far Dynamo Kiev are the only side to make a realistic offer for him – a season's loan – but the player is understood to have resisted it.

Portsmouth still believe that they can sign the Chelsea right-back Glen Johnson before the end of the transfer window.

The 23-year-old was on loan at Fratton Park last season but would be permitted to return on a permanent deal after Chelsea signed Barcelona's Juliano Belletti.