Liverpool are trying to sign Colombia winger Luis Diaz from Porto in the current transfer window. The deal, if completed, is expected to be worth €45m (£37m) plus a maximum of €15m in potential bonuses.
The 25-year-old had been linked with a move to Tottenham, who reportedly had a bid of around £38m rejected.
Diaz was Liverpool boss Jurgen Klopp’s first choice for the summer when the asking price would have been €60 million (£49.9m).
However, with Liverpool moving late because of the prospect of missing out on Diaz altogether, the proposed move is far from straightforward. The forward is currently with his national team for World Cup qualifying matches; Colombia play Peru on Friday before an away game against Argentina on Tuesday, 1 February.
Liverpool will send a delegation to Argentina to conduct a medical as they try to get the move completed before the January transfer window closes at 23:00 GMT on 31 January.
Diaz has played against Liverpool twice in the Champions League this season, with Porto losing 5-1 and 2-0 in the group stages of the competition.