Chelsea have completed the signing of Olivier Giroud from London rivals Arsenal.
The Frenchman's agent arrived in London on Wednesday morning to thrash out the final details of the deal taking him to Stamford Bridge on an 18-month deal for an undisclosed fee, believed to be around £18m.
His move to Chelsea was confirmed hours after Arsenal completed a club-record transfer for Pierre-Emerick Aubameyang from Borussia Dortmund.
Speaking to Chelsea's official website, Giroud said: "Chelsea is one of the biggest teams in the Premier League. They have won maybe the most trophies in the last six or seven years. It's a massive club and I am proud to sign for Chelsea, and I'm looking forward to playing."
Dortmund have signed Chelsea striker Michy Batshuayi on a season-long loan deal on Deadline Day as a direct replacement for Gabon international striker Aubameyang.
Giroud made his final appearance in an Arsenal shirt on Tuesday night, coming off the bench in the Gunners' 3-1 loss to Swansea at the Liberty Stadium.
At the final whistle the France international ran over to the away end and applauded Arsenal's travelling support before beating his chest.
Giroud joined Arsenal in the summer of 2012 after two seasons with Ligue 1 side Montpellier, where he scored 39 goals in 85 appearances.
The 31-year-old has fallen down the pecking order at Arsenal and has been restricted to just one Premier league start this season.
Giroud leaves the Emirates Stadium after scoring 105 goals in 253 appearances for the Gunners.