Michael Ballack's agent says the German captain could be a Chelsea player before the beginning of this summer's World Cup in his home country. Michael Becker said Chelsea were the only club he was talking to about the 29-year-old, who will be out of contract at Bayern Munich in May.
"The transfer window opens in May and the World Cup is coming up," Becker told BBC Sport.
"I think there is definitely something happening before the World Cup."
Becker confirmed that other clubs were interested in Ballack, with Inter Milan and Real Madrid among those linked with the midfielder.
But he stressed: "There is interest from other clubs but Chelsea are the only club we are talking to at the moment.
"Right now we are exclusively talking to Chelsea."
Blues boss Jose Mourinho has publicly stated his desire to bring Ballack to Stamford Bridge, saying that he would love to see the German star linking with Frank Lampard in the heart of Chelsea's midfield.
On Monday, he told German newspaper Bild: "I want him. He has said he needs time before making a decision. I respect that. Now it's up to him."
Lampard has been linked with a summer move to Barcelona with Ballack's arrival being seen in some quarters as a signal of the England international's possible departure from Chelsea.
But Mourinho added: "For me Ballack is one of the best players in the world.
"He's very intelligent, tactically very strong and he scores a lot of goals.
"For me in Europe there's only Frank Lampard who plays at that level. The two would form a dream pair.
"They're the two best players in the world in their category."
Ballack is said to want a four-year �120,000-a-week contract.