Manchester United are watching Sporting CP defender Goncalo Inacio leading up to the January market.
The Sun says United have dispatched a scout to Lisbon to shadow the Portugal international.
United manager Erik ten Hag is in the market for a new centre-half and Inacio is on his shortlist of options.
The scout has already checked on Inacio three times this season. He was at Sporting's game at the weekend and will also take in this Thursday's Europa League clash with Atalanta.
Inacio's contract at Sporting carries a 60m buyout clause.