Misfiring Chelsea bank on Joao Felix to spark forward line
The 23-year-old, who signed for a reported fee of 11 million euros ($12 million), will bolster the attacking options for manager Graham Potter, whose injury-hit squad is languishing in 10th spot in the table.
Chelsea tweeted "the artist has arrived", welcoming the Portugal international, who had also been linked with Arsenal and Manchester United.
"Chelsea is one of the great teams in the world and I hope to help the team reach their objectives, so I am very, very happy to be here and very excited to play at Stamford Bridge," Felix said in a club statement.
Felix joined Atletico from Benfica in 2019 for 126 million euros, making him one of the most expensive players of all time.
He has scored 34 goals in 131 appearances for the club, winning La Liga in 2021.
He also featured in Portugal's run to the World Cup quarter-finals in Qatar last month, scoring in the 3-2 victory against Ghana in the group stage.
Since then he has played twice for Diego Simeone's team, scoring in a 2-0 win against Elche on December 29 - taking his tally to five for Atletico this season.
Atletico confirmed on Wednesday that Felix had extended his contract with them for one more season, until June 2027.
"From Atletico Madrid we wish Joao Felix every success in this new professional stage," the Spanish club said in a statement.
'World-class'
Atletico CEO Miguel Angel Gil Marin last month described Felix as a "world-class talent" but said a number of factors, including his relationship with Simeone, meant the club should look at other options for the player.
"Personally, I would love him to continue but I think that right now the player has other ideas," he said.
Felix follows Benoit Badiashile, David Datro Fofana and Andrey Santos in joining Chelsea during the January transfer window.
The club's new American owners, who took over last May, have spent more than £300 million ($365 million) on new players to improve a squad that finished third in the Premier League last season.
But despite the heavy spending, Chelsea have endured a turbulent season, sacking manager Thomas Tuchel in September just seven games into the new campaign and replacing him with Potter.
The former Brighton boss has failed to turn things around at Stamford Bridge, though he has had to contend with a debilitating injury list.
Chelsea are 10 points adrift of a top-four spot in the Premier League after a miserable run of just one win in eight league games.
They are also out of both domestic cup competitions after a humiliating 4-0 defeat to Manchester City in the FA Cup third round at the weekend.
But the 2021 European champions are still in the Champions League and play the first leg of their last-16 tie against Borussia Dortmund next month.
