Joao Pedro could play in Chelsea's Club World Cup game with Palmeiras after completing his move from Brighton.
The Brazil forward has signed a seven-year contract in a deal worth £60m.
The 23-year-old flew from his homeland to the United States to undergo a medical and is now available to play in Saturday's quarter-final against Palmeiras (02:00 BST) in Philadelphia.
The Fluminense youth product scored 30 goals in 70 games for Brighton after joining from Watford in 2023 for just under £30m, which at the time was a club-record fee.
Chelsea have also had a £55m bid for English winger Jamie Gittens accepted by Borussia Dortmund.