Chelsea have confirmed they have completed the signing of Willian from Anzhi Makhachkala.
The 25-year-old was granted a work permit earlier today and having completed his medical over the weekend has now been unveiled by the west London club.
A statement on the club's official website read: "Chelsea Football Club is delighted to announce the signing of Willian.
"The 25-year-old Brazilian was today (Wednesday) granted a work permit and has signed a five-year contract, having moved to England from Russian club Anzhi Makhachkala. He will wear the number 22 shirt."
Willian said he was delighted to have sealed his move to Chelsea, describing his switch as a "dream" move.
"I'm very happy to be here, it's been a dream of mine to come and play here," he said.
"Chelsea are one of the best clubs in the world, and now I'm going to play for one of the best managers in the world, so I'm very happy and looking forward to it."
Tottenham had been on the verge of completing a deal for the talented forward, before Chelsea launched an audacious late swoop to secure his services.
The former Shakhtar Donetsk playmaker, who scored twice for the Ukrainian outfit against Chelsea in the Champions League last season, has two caps for Brazil and heads to Stamford Bridge having only joined Anzhi Makhachkala in January.
The Russian club has been forced to sell of most of its major stars as part of a cost-cutting exercise, which could see forward Samuel Eto'o join his former team-mate at Chelsea before the transfer window closes on Monday.