Claudio Pizarro has admitted he would only want to come back to Chelsea if he could play more regularly.
The Peru international joined the Blues from Bayern Munich in the summer of 2007 but he was rarely given opportunities in the starting XI.
He was allowed to link up with Werder Bremen on loan before the start of the current campaign and has proved to be a prolific goalscorer in the Bundesliga.
Pizarro is due to return to Stamford Bridge at the end of the season but he does not relish the prospect of sitting on the substitutes' bench again.
"I need to play," Pizarro told El Comercio newspaper.
"I am not 22 or 23-years-old and prepared to say I will go to Chelsea to be on the bench. I am in good form to play, not to be a substitute."
Pizarro, who is prepared to wait until May to make a decision, believes he could be successful in the Premier League.
He added: "The English league is not a finished chapter, but I would have to think about going back to Chelsea.
"I want to play and win titles. If I am given an offer, I would think about that, but I am not in a hurry."
Pizarro played for Werder Bremen between 1999 and 2001 and he concedes he would be open to staying at the Weserstadion.
"It is a possibility," he added. "I love this city, their people, the new guys I've met, the coach and the board.
"Playing here again is about more than football matters. I've been surprised by how much people love me here. It is amazing and I didn't notice that when I came here for the first time."