Arsenal reportedly had scouts in attendance to watch Porto midfielder Ruben Neves during his team's clash against Pacos Ferreira at the weekend.
Porto came from 1-0 behind to win the match 2-1 on home soil in a game where Neves played the full 90 minutes in the middle of the park.
According to The Metro, Arsenal sent scouts to watch the Portuguese midfielder as they consider making a £22m offer for the in-demand 18-year-old.
Neves, who has been linked with a number of European clubs since breaking into the Porto first team, has already made more than 30 league appearances for his current club.
The teenager represented Portugal at every youth level from the Under-16 team before stepping into the senior side earlier this year.