Romelu Lukaku has arrived in London to complete his £97.5m (€115m) transfer to Chelsea from Inter Milan.
The 28-year-old landed in Biggin Hill Airport on Wednesday evening after a stop in Monte Carlo.
He underwent the first part of his medical in Milan after Chelsea agreed in principle a club-record deal to re-sign the striker.
The paperwork is now with club lawyers, and once that is formalised, Lukaku is expected to sign a five-year contract, worth £200,000 a week.
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Inter have previously rejected two offers from Chelsea for the Belgium international, the second of which was worth £85m (€100m) plus left-back Marcos Alonso.
Meanwhile, Roma have agreed a £34m deal to sign Tammy Abraham from Chelsea, according to Sky in Italy.
The 23-year-old striker must now decide if he wants to join the Italian club, who are managed by former Chelsea boss Jose Mourinho.
Arsenal are also interested in Abraham, but Chelsea's preference is to sell him to a foreign club, making a move to their London rivals less likely.
Lukaku left Chelsea in 2014 after making just 15 appearances there following his arrival at Stamford Bridge from Anderlecht in 2011.
One of the most prolific strikers in Europe, Lukaku scored 87 goals in 166 games for Everton between 2014 and 2017 and found the net 42 times in 96 appearances during his two years at Manchester United before signing for Inter in 2019.
He scored 24 goals in Serie A last season, helping Inter to their first Scudetto in 11 years as the club put an end to Juventus' nine-year reign as Italian top-flight champions.
Chelsea will be keen to conclude the deal before 11pm on Tuesday so the player can be registered by UEFA to be considered for the Super Cup against Villarreal on Wednesday.
When the deal is completed, it will make Lukaku the most expensive player in history in terms of combined transfer fees, standing at a staggering £308.5m - over £30m more than Neymar in second (£271.7m).
Tuchel: Lukaku the profile we're looking for
Chelsea head coach Thomas Tuchel was reluctant to admit a deal for Lukaku was close, but did stress the No 9 role is an area the club are looking to strengthen after Olivier Giroud left the club to join AC Milan.
"We lost Olivier Giroud who played a crucial role in the club," Tuchel told Sky Sports. "He was the kind of profile who likes to play with his back to goal, who likes to hold up balls, who creates space for Werner, Havertz, Pulisic; who is ready to fight physically with defenders.
"This is the kind of profile that we don't have in our squad right now and that we are looking for. It's still not the moment to talk about names because we have nobody signed yet and we will show all the respect to other clubs.
"Romelu is one of the guys like Haaland at Dortmund, Lewandowski at Bayern, Harry Kane at Tottenham, who is a real No 9 who loves to score and who has a presence in the box. That is not a secret. The sentence [Tuchel describing Lukaku as a 'fantastic player'] is easy to repeat for any coach in the world.
"But [his] is the kind of profile we're looking for and if it is possible to convince agents and clubs, we will do our best."
Tuchel also stressed the need to improve after "big signings" elsewhere in the form of Jack Grealish to Manchester City and Jadon Sancho to Manchester United.
"They are big signings and we are also trying to improve the squad; at the same time we give all our energy to the guys that we have - it's our goal to improve the group we have," Tuchel added.
Chelsea's lost stars
The imminent return of Romelu Lukaku to Stamford Bridge highlights the wealth of talent that Chelsea have allowed to leave the club in the last decade.
Chelsea sold Lukaku for £28m to Everton in 2014 and are now buying him back from Inter Milan for £97.5m - a £69.5m loss.
Here are some of the other stars that also failed to make the grade at Chelsea, but have gone on to have stellar careers elsewhere.
Chelsea sold Salah to Roma for £12m in August 2016. Liverpool bought him 10 months later for £34m. In the current market, despite being 29 years old, his value would certainly be in excess of £100m.
Kevin De Bruyne
Only made three Premier League appearances for Chelsea under Jose Mourinho. He was sold to Wolfsburg for £18m in January 2014, and moved to Manchester City for £55m, 18 months later. Current market value is well in excess of £120m - not that City would consider selling him.
Released by Chelsea as a 14-year old after seven years at the club. Heavily linked with a return to Stamford Bridge, but reports suggest it would take more than £70m for West Ham to be interested in selling.
Chelsea made £20m when they sold Ake to Bournemouth in June 2017. That seemed good business at the time, though three years later, Manchester City paid £41m for him.
Eden's younger brother made just one appearance for Chelsea's U21s before being shipped out on loan to Zulte Waregem. Borussia Monchengladbach paid Chelsea a nominal fee for his services, before Borussia Dortmund shelled out £30m for the attacking midfielder in the summer of 2019.
Chelsea paid £21m to sign him back from Benfica in January 2014, two-and-a-half years after sanctioning his sale for £4.5m. They would go on to make a profit on the midfielder when they sold him to Manchester United for £40m in 2017.
The evolution of Lukaku explained
His Belgium national team coach Roberto Martinez was among those to suggest there has been an evolution in Romelu Lukaku's game and one statistic highlights it best. Nobody in Italy provided more assists from open play than Lukaku did for Inter last season.
It is a statistic still viewed with scepticism by some and it is true that Lukaku's tally of 11 included a number of straightforward square passes and lay-offs. But other goals highlight the awareness, intelligence, vision and touch that carried Inter to the title.
It is a level of performance that has persuaded Chelsea to bring him back to Stamford Bridge one decade on from signing his first contract at the club. Lukaku, 28, returns at the peak of his powers, never better prepared to make a big impact on the Premier League.
Inter fans protest against owners - "Zhang, the time is over"
Inter must decrease their wage bill this summer and title-winning manager Antonio Conte left the club in May amid concerns about plans to reduce his budget.
Lukaku was not involved as Inter won 2-0 in a friendly away at Parma on Sunday evening - a match that witnessed prolonged protests against the club's Chinese owners over the planned sale and general cost-cutting strategy.
President Steven Zhang was the target of most of the anger with banners at the game saying "Zhang, the time is over" and "Zhang, if you want to save Inter you have to leave".
Chelsea are eager to sign a world-class centre-forward during the transfer window and Erling Haaland of Borussia Dortmund is another target the Blues have been interested in.
Meanwhile, with Lukaku set to depart the San Siro, Inter Milan are in talks to sign Roma forward Edin Dzeko and are offering the Bosnia and Herzegovina international a two-year deal.
Inter want to sign two forwards to replace Lukaku and one of their other targets is Atalanta's Colombia international Duvan Zapata.
If Atalanta sell Zapata, they will try to sign Tammy Abraham from Chelsea.
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