Manchester United have reached an agreement to sign Argentina defender Marcos Rojo from Sporting Lisbon.
United said the deal, which Sporting report is worth £16m, is subject to a medical, and personal terms being agreed.
Sporting have also confirmed Nani, 27, is returning on loan, seven years after the winger joined United from Lisbon.
Left-sided defender Rojo, 24, played in six games as Argentina reached the 2014 World Cup final in Brazil.
Last week he refused to train with Sporting because of his frustration at not being allowed what he described on Argentine radio as a “dream” move to United, although he subsequently apologised.
“A further announcement will be made when the process is complete,” said United in a message on the club’s Twitter accounton Tuesday.
In a statement released to the Lisbon stock exchange, Sporting set out the payment schedule agreed with United for the player.
They will receive £8m immediately, with further instalments of £4m being paid on 1 December this year and 1 July, 2015.
In addition they will get 20% of any sell-on fee for Rojo over £18.4m.
Rojo, who joined Sporting from Spartak Moscow in July 2012, missed the Portuguese club’s first league game of the season last weekend.
United have been searching for a central defender following the summer departures of Nemanja Vidic and Rio Ferdinand, with Rojo’s versatility making him a good fit for United manager Louis van Gaal’s preferred 3-5-2 system.
Nani at Manchester United
Premier League titles: Four
Champions League titles: One
Appearances: 230 Goals: 41
Was nominated for the 2011 Ballon d’Or award
United’s player of the year after helping win 2011 League title
Van Gaal missed out on Thomas Vermaelen earlier this month after the Belgian opted to join Barcelona from Arsenal.
Nani, who has won 78 caps for Portugal, is understood to have joined Sporting on a season-long loan, but neither club has released details of the winger’s move.
The Cape Verde-born player spent four years at Sporting after leaving Real Massama in 2003.
After joining United in 2007, he made 230 appearances in all competitions, scoring 41 goals.