Sport Witness, as quoted by the Daily Mirror, says that the Red Devils sent representatives to the Braga Municipal Stadium to watch Benfica’s emphatic 4-0 win over Braga on Sunday.
The same story says that the scouts were specifically taking a look at Dias and Luis, who are widely regarded as two of Benfica’s brightest prospects.
Defender Dias, 22, has already won 11 international caps for Portugal, while Luis, 20, has been a regular performer since his breakthrough campaign last term.
According to the same story, however, Manchester United could be set to face competition for both players if they are indeed interested in signing them.
The article says that representatives from several other clubs also attended the fixture at the weekend, including Lyon, Bordeaux, Sevilla, Villarreal, Celta Vigo, Atalanta as well as Premier League new boys Norwich City.
Manchester United are likely to now start turning their attention towards the January transfer window as they look to strengthen their squad at the half-way point of the season.
Meanwhile, the Red Devils will return to Premier League action after the international break when they host Leicester City at Old Trafford on Saturday 14 September.
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