The twice-capped 25-year-old was finally granted a work permit on Wednesday to complete his move from Russian club Anzhi Makhachkala after agreeing a five-year contract with the Blues.
And with their attempts to sign Wayne Rooney from Manchester United seemingly floundering, Chelsea were reported to be on the verge of signing another Anzhi player in the form of Cameroon striker Eto'o.
On Thursday morning pictures emerged of the 32-year-old, who has been widely linked with a move to Stamford Bridge over the last few days, apparently arriving at London St Pancras station on Wednesday night.
Chelsea are keen to increase their attacking options, while Anzhi have been offloading players after owner Suleyman Kerimov decided to reduce his spending at the Dagestan club.
Former Barcelona star Eto'o flourished under Chelsea boss Jose Mourinho's guidance when the pair were at Inter Milan together.