Manchester United have had a bid, believed to be in the region of £37m, accepted by Chelsea for Spanish midfielder Juan Mata.
The 25-year-old will have a medical on Thursday before completing a move to the Premier League champions.
Mata is expected to sign a four-and-a-half year deal at Old Trafford.
The Spain international, who has won 32 caps, said goodbye to team-mates and staff at Chelsea's Cobham training ground on Wednesday.
United continue to deny having made a bid for the playmaker, but it is understood they have made an offer through intermediaries working on the deal.
Should the deal go through, it would break United's previous record transfer - the £30.75m they paid Spurs for Dimitar Berbatov in September 2008.
Mata, 25, has been linked with a move away from Stamford Bridge after struggling to hold down a regular starting place under Jose Mourinho.
On Tuesday, Chelsea insisted that Mata, who had been voted the club's player of the year two seasons in a row, was not for sale.
But the player, who was part of the Spain squad which won the World Cup in 2010 and European Championship in 2012, has been substituted in nine of his 13 Premier League appearances for the Blues this season, prompting speculation other clubs could bid for him in the January transfer window.
United have made no secret of their plans to rebuild their team under David Moyes and are prepared to pay a premium for top players if it means securing them now rather than waiting until the summer.
"A lot of the work we are doing now is in preparation for the summer," Moyes told United's matchday programme ahead of their League Cup semi-final second-leg against Sunderland on Wednesday.
"If we can do any business now then we will certainly try to do it, but I will not compromise the standards required for a player that can come into this club and help improve it."
Chelsea boss Mourinho, 50, said last week that while he understood it was "hard" for Mata to sit on the bench, the Spaniard still had a "big role" to play at the club.
The Portuguese has trusted Eden Hazard, Oscar and summer signing Willian in attacking roles this season and while his relationship with Mata is healthy, he has conceded Chelsea's system does not suit the player.
"There are fantastic players, but sometimes the fantastic players are more fantastic to a certain system and less fantastic in a certain model of play," Mourinho told BBC Sport's Football Focus.
"He is an unbelievable player and a fantastic boy who is trying his best to adapt."
Chelsea paid £23.5m to sign Mata from Valencia in 2011. The former Real Madrid youth player had impressed during four seasons with the Spanish club and began life in England by scoring 13 goals in his debut season as Chelsea won the FA Cup and Champions League.
He followed it up with 20 goals in the 2012-13 season as Chelsea lifted the Europa League under Rafael Benitez but, since Mourinho returned for his second spell at the club, Mata has seen his playing time limited.
He was substituted 53 minutes into the Blues' 3-0 win at Southampton on New Year's Day, his last appearance, and was visibly frustrated when taking his place on the bench as Mourinho stood in his technical area.