Premier League scouts are flocking to check on Olympiakos star Diogo.
Chelsea and Liverpool have both requested VIP seats for Sunday's match on Sunday when they face local rivals AEK Athens, while Middlesbrough dispatched a scout to watch the midweek clash with Danish side Nordsjaelland.
Boro had Derek Bragg of The Scouting Network at the game to watch Diogo and Sebastian Leto, currently on loan at the club from Liverpool, for the home side and Martin Bernburg of Nordsjaelland.
Bragg admitted that both Diogo and Leto - who was denied a work-permit to play in England earlier this summer - would both make impacts in England.
"Diogo and Leto are very good players," he told the Greek press.
"Both of them can make it at the Premier League. I watch them and I will keep watching them.
"They have good chances to make a brilliant career in England."
Bragg, though, admitted he was left disappointed that Bernburg did not take part in the game.
Diogo only joined Olympiakos in the summer when they paid Portuguesa €9million (£7million) for him, and has been in great form since moving to Greece, although the Brazilian youth international was already well known around Europe for his potential.
Arsenal boss Arsene Wenger was a confirmed fan of the 21-year-old and tried on more than one occasion to sign him earlier in his career.