Chelsea have completed the signing of Enzo Fernandez from Benfica for a British-record fee of €121m (£106.3m).
The Argentina international, who was named the best young player of last year's World Cup in Qatar, has put pen to paper on an eight-and-a-half-year contract that will keep him at Stamford Bridge until 2031.
Chelsea were linked with Fernandez throughout the January transfer window, but initially looked to have missed out on their man when Benfica refused to sell earlier this month, despite Fernandez making it clear that he wanted the move.
However, club officials travelled to Portugal to revive the deal towards the end of the window, with the two parties finally coming to an agreement over a payment structure late on deadline day.
The Blues still needed a deal sheet and an extension to force the transfer over the line, but Benfica have now confirmed the sale.
Chelsea are expected to pay the record fee of more than £106m over six instalments, with the first of those being a lump sum of €34m (£29.9m).
Fernandez will fly to London on Wednesday to meet his new teammates, and could make his debut for the club in the West London derby against Fulham on Friday.
Benfica were desperate for the midfielder to stay at the Estadio da Luz until at least the end of the season, but Fernandez was keen to leave and pushed for the exit again once Chelsea rekindled their pursuit.
The deal sees the 22-year-old surpass Manchester City's Jack Grealish as the most expensive player in British football history.
It also continues Chelsea's extraordinary spending since being taken over by a consortium led by Todd Boehly, with the Blues having now splashed more than £600m on new players in the last two transfer windows.
More than £300m has been spent by the West Londoners in January alone, with Mykhaylo Mudryk, Benoit Badiashile, Noni Madueke, Malo Gusto, Andrey Santos, David Datro Fofana and Joao Felix joining Fernandez as new arrivals at Stamford Bridge.
Fernandez's move is also good news for River Plate, who will receive £26.7m from the fee due to their 25% sell-on clause in his contract.
