Chelsea have completed the £21million signing of Pedro from Barcelona on a four-year deal.
The Blues swooped with the Spanish winger on the brink of moving to Premier League rivals Manchester United.
Pedro, 28, expressed his delight upon arriving at Stamford Bridge after a year out of favour with the Catalan giants.
He said before training with his new team-mates: ‘I am very happy to be here. I am very excited to start my adventure at Chelsea and I am here to keep winning titles.
'Thanks to the club and the supporters for giving me the opportunity to put the blue shirt on.’
Pedro was quick to nail his colours to the Chelsea mast by changing his Twitter cover photo to a section of Blues supporters with a banner reading 'Pride of London'.
Pedro becomes Chelsea boss Jose Mourinho's fourth new signing of the summer after Asmir Begovic, Radamel Falcao and Abdul Baba Rahman.
United looked to have sealed the deal to take Pedro to Old Trafford, with executive vice-chairman Ed Woodward travelling to Barcelona to tie up the deal.
However, Sportsmail understands the World Cup winner was underwhelmed with United's advances, his camp unaware of Woodward's trip.
Mourinho stole a march in the chase by calling up the winger personally to convince him to move to west London.
The Premier League champions have been sprung into transfer action after enduring a dreadful start to the season on and off the pitch, culminating in a 3-0 defeat at Manchester City.
United boss Louis van Gaal was never sold completely on the idea of signing Pedro, with the Manchester club revealing they pulled out of any deal on Tuesday.
They are now looking at other options, such as Southampton's Sadio Mane.
Barcelona confirmed they had agreed a fee with Chelsea, stating their thanks for Pedro's eight years of service at the Nou Camp.
Chelsea struck a deal for £21m with £19m paid up front, more than United offered.
He becomes the second recruit for the champions since Sunday's sobering 3-0 defeat at Manchester City, after £22m left back Rahman joined from Augsburg.
Pedro has sought a move from Barcelona, where his opportunities have been limited by the dazzling presence of Lionel Messi, Neymar and Luis Suarez.
Mourinho rejected the chance to sign him in January, when Chelsea preferred to spend £27m on Juan Cuadrado from Fiorentina because he was not cup-tied in the Champions League.
Cuadrado has been a huge disappointment and will be offered the chance to leave on loan.
Portuguese tactician Mourinho will hope Pedro can inject the required pace, urgency and goals into a team who have opened the season in sluggish style, taking one point from two games.
Pedro was delighted when Chelsea revived their interest. He was said to have been unconvinced about a move to Old Trafford, perhaps detecting Van Gaal's doubts about his suitability.
United's take on the matter on Wednesday night was that they withdrew from the deal on Tuesday when the manager decided he didn't want the Barcelona player after all.
It seemed a strange explanation, given chief executive Woodward had been in Catalonia as recently as Monday.
United took their search for pace and creativity towards Mane, the 23-year-old Senegal striker who scored 10 goals in 30 games for Southampton last season.
Saints were quick to issue a firm rebuke. 'Mane is a key part of our team and our planning for the future,' said a source inside the club. 'He wouldn't be sold.'
Chelsea new boy Pedro, on the other hand, is expected to make his Premier League debut when the Blues face West Brom at The Hawthorns.
Pedro won 20 major titles and scored 99 goals during his time with Barcelona - including three Champions League winner's medals and five La Liga titles.