Chelsea have completed the signing of Barcelona forward Pedro in a deal believed to be worth £21million.

The Premier League champions stepped in to sign the Spain international after Manchester United withdrew their interest.

Chelsea announced the deal on their website, but gave no information regarding the transfer or the length of the contract signed by the 28-year-old.

Pedro said on chelseafc.com: "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 had been a target for United throughout the summer, with the club's executive vice-chairman Ed Woodward flying to Catalonia on Monday in an attempt to seal a deal for the player.

But things changed rapidly on Wednesday as it emerged that Louis van Gaal had withdrawn his interest while Chelsea were moving to steal a march on their rivals.

Jose Mourinho has acted quickly and decisively in the transfer market after Chelsea endured their worst start to a season in 17 years.

Shortly after their 3-0 defeat at Manchester City, Chelsea signed left-back Baba Rahman from Augsburg for £21million, and Pedro's arrival gives Mourinho's side fresh attacking intent.

The Blues also hope to conclude the signing of Everton defender John Stones before the transfer window shuts on September 1.