The double acquisition was seen as a further sign of coach Jose Mourinho's increasing desire to win the Champions League for the second time in his career.

Already a winner with Porto, Mourinho is determined to repeat the feat at Stamford Bridge - and has utilised the millions provided by billionaire owner Roman Abramovich to good effect.

But Chelsea's success in winning the Barclays Premiership for the last two seasons has brought accusations that Abramovich 'bought' the title with his seemingly unlimited spending power.

Ballack, preparing for the eagerly-awaited visit of Barcelona next week, is determined the same thing will not happen if Chelsea win the biggest trophy in Europe.

He said: "Chelsea are not the only team buying players. Sometimes they make bigger purchases, and that stands out - but other teams buy big as well.

"Real Madrid, Italian teams, German teams - they all buy players. But if you are not successful then you are just a buyer of players. Not Chelsea. You don't just pick any players; you have to pick the right players to fit together and get a good mood in the team.