Chelsea look set to continue their policy of transfer spending ahead of the 2023/24 Premier League season with Christopher Nkunuku joining from RB Leipzig.
Nkunku has been heavily linked with a move to Stamford Bridge since the start of 2023 amid rumours a deal had been agreed in January and his switch has now been completed.
The 25-year-old becomes the first signing of the Mauricio Pochettino era as the Argentinian looks to make a positive start to life back in English football.
Nkunku is set to be joined by more new faces in the coming weeks as club owner Todd Boehly prepares to fund Pochettino's squad revamp.
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Christopher Nkunku to Chelsea transfer fee
Chelsea have spent eye-watering sums since Boehly took control of the club in May 2022, setting records in the 2022/23 summer and winter transfer windows.
The estimated £240m/$307m spent by Thomas Tuchel last summer broke the previous overall Premier League record for a single transfer window. with Graham Potter's £281m/$360m January splurge breaking more new ground.
Pochettino is unlikely to be spend quite as much as his predecessors, but a deal to sign Nkunku includes a transfer fee of £52m/$66.4m, as per reports from BBC Sport.
Christopher Nukunku Chelsea contract
Chelsea have set out their commitment to Nkunku, with a six-year contract agreed up until the end of the 2027/28 season.
"I am incredibly happy to be joining Chelsea", Nkunku said in his first interview with the club.
"A big effort was made to bring me to the club and I'm looking forward to meeting my new coach and teammates and showing the Chelsea supporters what I can do on the pitch."
Nkunku is a Blue! 🔵 pic.twitter.com/NASfDOG0Xg
— Chelsea FC (@ChelseaFC) June 20, 2023
Christopher Nkunku shirt number at Chelsea
Nknuku has worn the No.18 shirt at RB Leipzig for the last four seasons following his move to Germany from Paris Saint-Germain.
Chelsea's current No.18, Armando Broja, did not make a single appearance last season after returning from a 2021/22 loan spell at Southampton.
Nkunku's first choice would be to retain his favoured number, with Chelsea open to either reassigning Broja a new number or potentially selling the Albania international.
If Nknuku is unable to stay as No.18, he may take over the No.7 if N'Golo Kante moves on.
What country does Christopher Nkunku play for?
Nkunku is a France international player with 10 international caps won for Didier Deschamps' side, but he missed out on a place in their 2022 World Cup squad due to injury.
Chelsea's new star is from the same area of east Paris as Paul Pogba, the commune of Lagny-sur-Marne, and represented France at four underage levels before making his senior debut in 2022.
Christopher Nukunku Chelsea debut
With Chelsea completing a early summer deal for Nkunku, he will join up with Pochettino's squad for their full preseason camp, with his contract formally beginning on July 1.
With preseason training due to start from early July, Nkunku is set to be included in Chelsea's USA tour, with a potential debut in their opening fixture in North Carolina against Ryan Reynolds' Wrexham on July 19.
Christopher Nkunku's Chelsea position
Nkunku has superb tactical and positional flexibility, which Pochettino will look to utilise when assessing his best role for Chelsea.
The player himself has previously stated his favoured slot in as an advanced attacking/No.10-style midfielder, behind the main striker, but Leipzig used him in both positions.
A tally of 16 Bundesliga goals, and 23 overall, in 2022/23 underlines his ability to score from a deeper starting role with 12 of his goals last season coming from a No.10 spot.
Christopher Nkunku's RB Leipzig career by numbers:
— Squawka (@Squawka) June 20, 2023
◉ 172 games
◉ 70 goals
◉ 45 assists
◉ 2 trophies
Now he's a Blue. 🎈 pic.twitter.com/O45ryK7Q5Q
He ended the campaign as the Bundesliga's joint-top scorer, alongside Werder Bremen's Niclas Füllkrug, an impressive feat for a player not operating solely as a striker.
Pochettino is already stacked with options in attacking midfield, but with Mason Mount linked with an exit, Nkunku would slot in as a central forward-thinking midfielder, flanked by Enzo Fernandez and Mateo Kovacic/Conor Gallagher.
Chelsea are still in the market for a central striker, which Nkunku can cover, alongside doubts over Kai Havertz's future at Stamford Bridge.
RB Leipzig switched between approaches in 2022/23 and Nkunku can also play as a pure No.10, with two holding midfielders in behind and pace out wide, as he did with Timo Werner and Dominik Szoboszlai in Germany.