Although the fee was not disclosed by the clubs involved, British and American media outlets reported that Chelsea had made an offer of £97.5 million ($135 million) for Lukaku.
The Belgian joined Chelsea from Anderlecht in August 2011, but left the West London club for Everton in 2014 after making just 15 appearances.
“I am delighted and blessed to be back in this wonderful club,” Lukaku said in a statement to the club. “It has been a long journey for me: I came here as a kid with a lot to learn, now I am coming back with a lot more experience and more mature.
“The way the club is perfectly fitting my ambitions at the age of 28 and coming away winning Serie A. I think this opportunity comes at the right time and hopefully we can achieve a lot of success together.” Can… the challenge is to try to help the team win a few more trophies. I can’t wait to get started and help the club achieve more success.”
Lukaku was one of the most prolific strikers in the Premier League, scoring 87 goals in 166 games for the Merseyside club between 2014 and 2017.
In July 2017, Lukaku moved to Manchester United, where he added 42 goals in 96 matches to his goal-scoring tally.
Lukaku’s stay, however, was short-lived, with the talisman sealing a move to Italian giants Inter Milan in August 2019.
Lukaku’s return to Stamford Bridge will add even more firepower to an attacking line-up that already includes German duo Kai Havertz and Timo Werner, England’s Mason Mount and American Christian Pulisic.
Chelsea director Marina Granovskia said in a club statement: “Romelu Lukaku is one of the best strikers and goalscorers in the world. We are very pleased to have him back at the club he loves, and to bring his talent to our Excited to be associated with a Champions League winning team.
“We definitely want to build on the success of last season, and Lukaku will play a big part in achieving our goals.”
After winning last season’s UEFA Champions League, Thomas Tuchel’s team will be eyeing a recapture of the English Premier League title, which they last won in 2017.
Chelsea will start the new Premier League season at home at Crystal Palace on Saturday.
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