Chelsea want to bring Didier Drogba back to the club on an extraordinary loan before the winter transfer window and they have started discussions aimed at making it happen.

The European champions, who sacked their manager Roberto Di Matteo on Wednesday morning, have grown so concerned at the form of Fernando Torres that they hope to secure a temporary reunion with Drogba.

The centre forward, who left Chelsea for Shanghai Shenhua in the summer, has reached the end of the Chinese Super League season and he has a window in December before he reports for the Africa Cup of Nations with Ivory Coast in January.

Drogba has asked Fifa for special permission to move on loan from Shanghai outside of the official transfer window and the game's governing body has confirmed that it is considering the request. "The Fifa administration services are looking into it," a spokesman said.

Even if Fifa relented and Chelsea were allowed to sign Drogba on a short-term contract, he could not play in their must-win final group match against Nordsjaelland on 5 December. Champions League teams must register their squad lists for the group stage with Uefa in September before their first match.

Drogba scored Chelsea's equaliser in the Champions League final against Bayern Munich last May, together with the winning penalty in the shootout, and he might have stayed at the club if they had offered him the two-year contract that he wanted. But Chelsea said that they intended to build the attack around Torres and Drogba left as a Bosman free agent.

Torres has struggled desperately in recent weeks and the nadir for him came on Tuesday night at Juventus, when he was dropped for the 3-0 Champions League defeat that precipitated the departure of Di Matteo, despite the club's only other recognised striker, Daniel Sturridge, being injured.

Chelsea are expected to move for a new striker in January, with Atlético Madrid's Radamel Falcao and Andre Schürrle of Bayer Leverkusen prominent on their wish list. But if Fifa allow it, Drogba could help them out until then.