Manchester United reportedly had scouts at Benfica's Champions League clash with Paris Saint-Germain last week to watch young defender Antonio Silva.
The 18-year-old has been with Benfica since 2016 and has made the breakthrough into the first team this season, featuring on nine occasions in all competitions.
Silva has made six appearances in the league this term, in addition to three outings in the Champions League, playing the full 90 minutes in Benfica's three matches with Maccabi Haifa, Juventus and PSG.
According to The Mirror, Man United scouts watched the teenager in action against the French champions, with the points being shared in a 1-1 draw in Portugal.
The report claims that the 20-time English champions are taking 'a big interest' in the Portugal Under-21s international, with the club looking to bring a young centre-back to the club.
There is allegedly a £13m release clause in Silva's current deal, which is due to run until June 2027, but Benfica are attempting to negotiate it higher due to the growing interest in his services.
Real Madrid are also believed to be closely monitoring the youngster, who again played the full 90 minutes against Rio Ave in the league on Saturday.
A January deal is said to be highly unlikely, but Man United are believed to be keen to explore the possibility of bringing him to Old Trafford during next summer's transfer window.
Silva is again expected to be in the starting XI on Tuesday evening, with Benfica making the trip to PSG in the Champions League.
Man United boosted their centre-back options over the summer with the arrival of Lisandro Martinez, with the Argentine joining the current crop of Raphael Varane, Harry Maguire and Victor Lindelof.
There remains uncertainty surrounding Maguire's long-term future in Manchester, though, as he continues to struggle for form.
Axel Tuanzebe and Phil Jones are also expected to leave Old Trafford on free transfers next summer, while Eric Bailly could complete a permanent switch to Marseille.
As a result, there should be space in the squad for the 20-time English champions to bring in a new central defender, with Ten Hag looking to the future.
Man United will be bidding to build on Thursday's 3-2 success over Omonia in the Europa League when they make the trip to Everton in the Premier League on Sunday night.
Ten Hag's side suffered a 6-3 defeat to Manchester City in the league last weekend, and Saturday's results have seen them drop into seventh position in the table. body check tags ::
