Samuel Eto'o is aiming to show Chelsea and Jose Mourinho that they were right to end their pursuit of Wayne Rooney.
The Cameroon striker has left Russian club Anzhi Makhachkala to sign a one-year deal and be reunited with Mourinho, who was his boss at Inter Milan.
Mourinho had been targeting Manchester United striker Rooney, but, after two rejected bids, Chelsea opted against lodging a third, instead signing Eto'o, who might have moved to Stamford Bridge during the Portuguese's first spell as boss.
"I've had a couple of opportunities to come to England before, including the first time Jose was here, but it didn't work out for one reason or another," Eto'o said on chelseafc.com.
"Since that time I have had a career where I have been lucky enough to win a lot of trophies in different countries, but one of my last dreams as a professional is to come and play in England and see if I can have the same success as in my previous clubs.
"I am very happy to be here but also anxious because I want to get playing as soon as possible."
The former Barcelona striker did not travel to Prague for Friday night's European Super Cup clash with Bayern Munich - neither did Willian, whose move from Anzhi was confirmed on Wednesday - but is eager to get into the action.
Eto'o will have to wait until after the international break to make his debut, with Everton away on September 14 the first opportunity.
The move might never have happened if Mourinho had received the indication from Rooney that he wanted to join Chelsea.
Speaking prior to confirmation of Eto'o's arrival, Mourinho appeared to have conceded defeat in the bid to capture the England striker, who played for United against Chelsea on Monday and afterwards praised the "fantastic" reception he received at Old Trafford.
Mourinho said: "I told you what I have to say. I think I (made it) very, very clear that we didn't start the process (a third bid).
"We have nothing more to say. He's a Man United player and no more than that."
Capturing Eto'o, who commanded wages reported to be in the region of £300,000 a week in Russia, is at odds with Chelsea's recent transfer policy of signing younger players. It also leaves a question mark over the futures of Demba Ba and Fernando Torres as Mourinho has made it clear four strikers is too many and that Romelu Lukaku is key for Chelsea's future.
Ba's place in the squad seems most at risk, but Torres has still to repay the £50million fee paid to Liverpool, as Mourinho admitted earlier this week.