Manchester United announced they have reached an agreement in principle to sign Real Madrid midfielder Casemiro in a deal worth up to a reported £60 million ($70 million).
The Brazilian has been offered a four-year contract with the option of a further 12-month extension, with the transfer subject to the agreement of personal terms.
United manager Erik ten Hag has been desperate to land a defensive midfielder since taking charge at Old Trafford and after failing to sign Barcelona's Frenkie de Jong.
The Red Devils have endured a horrible start to the season, sitting bottom of the table after embarrassing defeats against Brighton and Brentford.
The 30-year-old, who joined Real in 2013 and has been a key figure in midfield for the Spanish club, has won five Champions League titles.
"Manchester United is delighted to announce that the club has reached agreement with Real Madrid for the transfer of Casemiro," a statement from United said.
"The transfer is subject to the agreement of personal terms, UK visa requirements and a medical."
Ten Hag did not discuss the transfer during his press conference on Friday, but Real boss Carlo Ancelotti was more forthcoming when speaking to the media.
"I've discussed it with him this morning. He wants to try a new challenge, a new opportunity," Ancelotti said.
"The club understand it. With all he's done for this club and the person he is, we have to respect it. If he doesn't stay, we'll have an enormous sense of gratitude to him for all he's done. We have replacements within the squad."
Real Madrid said they will hold a "tribute and farewell" to Casemiro on Monday which will be attended by the club's president, Florentino Perez.
Casemiro's wealth of experience and success at the highest level will make him a certain starter instead of either Fred or Scott McTominay in central midfield.
He is unlikely to be available for United's next match against Liverpool at Old Trafford on Monday. Instead, Casemiro's debut could come at Southampton in the Premier League on August 27.
United are looking to get their campaign back on track at a time of intense pressure on the Glazer family. Protests are planned against the owners before and during Monday's clash with Liverpool and Sir Jim Ratcliffe has publicly declared his interest in buying the club.
Asked about the protests against the Glazer family, Ten Hag said: "I can only say the owners want to win and the fans, we want them behind the club.
"I can understand sometimes but I am not that long in the club that I can see all the backgrounds, but we have to be unified and fight together."
Anthony Martial has returned to training ahead of the game but his availability is unclear after injury, increasing the chances of Cristiano Ronaldo starting again.
