Chelsea have agreed a £47.5million fee with Manchester City to sign forward Raheem Sterling.
The 27-year-old started his medical in London on Sunday and it will continue into Monday, with Chelsea hopeful Chelsea a deal will be completed in time to allow the England forward to join the club's pre-season tour in the United States.
Sterling has remained Chelsea's top target this summer, even though the Blues were strongly linked with Leeds forward Raphinha and his fellow Brazilian Richarlison.
Sterling has agreed personal terms on a five-year contract with the option of a further 12 months and his medical will begin on Sunday afternoon.
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Sterling joined City from Liverpool for an initial £49m in July 2015 and has played a key role in their success under Pep Guardiola.
He has won four Premier League titles, one FA Cup and three League Cups at the Etihad Stadium, and scored 131 goals in 339 appearances for the reigning Premier League champions.
Sterling would offer Tuchel a guaranteed threat - he has directly contributed a combined 165 goals in the division in 320 appearances for Liverpool and City - as well as tactical flexibility and experience.
The 27-year-old believes he is in the decisive phase of his career and wants to make a significant contribution on and off the pitch.
The fact that City can cede two attackers to members of the 'Big Six' - Gabriel Jesus to Arsenal for £45m and Sterling to Stamford Bridge - without trepidation is a sign of their solid recruitment and the gap that exists between the clubs.
Why Chelsea appreciate Sterling's true value
Sterling wants greater minutes but also responsibility in this defining period of his career, and Chelsea are wanting a marquee signing to mark the start of a new era.
The move would not only benefit Chelsea. Sterling would improve on his understanding with England team-mates James and Mount, two players he can consult for a gauge on how Tuchel operates. Barcelona and Real Madrid have been linked but Chelsea are one of very few clubs who can afford his wages.
Tuchel will no doubt be attracted by Sterling's versatility across the forward line, capable of playing on either flank or through the middle as a false nine - a tactic the German has preferred over the conventional target man. Lukaku's return on loan to Inter Milan hastens talk of Sterling's arrival.
Chelsea won 21 men's trophies and 12 women's titles since Roman Abramovich's purchase in 2003. Todd Boehly has now replaced Bruce Buck as chairman, and prising a ready-made serial winner in Sterling would be a big opening statement.
Why is Sterling still underrated?
It is rare for a player to move between two top Premier League clubs at his peak - and rarer still that such a switch would be met with such ambivalence. Why is Raheem Sterling's proposed transfer from Manchester City to Chelsea seen this way?
City supporters seem relaxed about his future. That is surprising given that Sterling has scored, on average, 22 goals for the club across the past five seasons. Only Lionel Messi and Sergio Aguero - just four ahead - have scored more goals under Pep Guardiola.
But Chelsea fans are not greeting the reports with glee either. Sterling is 27 and has demonstrated that he can thrive in any position across the front three. What does it tell us about how the player is perceived that it is not being heralded as a major coup?
City and Chelsea in talks over Ake
Chelsea and Manchester City have also held talks over a deal for Nathan Ake.
Chelsea are in need of defenders after Andreas Christensen and Antonio Rudiger left this summer. The Blues showed interest in Juventus centre-back Matthijs de Ligt, but Sky Germany are reporting the defender wants a switch to Bayern Munich this summer.
Ake, 27, left Chelsea for Bournemouth in 2017 after an initial loan spell before a £40m move to City two years ago.
The Netherlands centre-back saw his game time limited at the Etihad, playing in just 14 Premier League games for Pep Guardiola's side last season.
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