Arsenal, Manchester United, Chelsea and Liverpool scouts were among a number of top European clubs who sent scouts to watch the O Classico between Benfica and Porto on Saturday night, according to reports in Portugal.
Benfica v Porto is the biggest game in Portuguese football and several top clubs sent their scouts to watch over the game.
Portuguese publication A Bola claim representatives from the likes of Barcelona, Juventus, Paris Saint-Germain, Valencia, Marseille, Lorient, FC Koln, Leicester City, West Brom and Brighton were all present for the game which ended in a 1-1 draw.
The Gunners have previously been linked with Porto midfield duo Danilo Pereira and Yacine Brahimi, although it is not clear whether the north London club sent their scouts to watch over the trio on Saturday evening.
It is highly likely that the Gunners will continue to send scouts to the big games around Europe as reports suggest that the club are looking to rebuild over the summer.