Marquinhos
The Brazilian teenager was signed from Sao Paulo for £3m in the summer, and he has already made an impression for the Under 21s in Premier League 2.
On his debut, Marquinhos scored the second goal and provided a superb assist for Miguel Azeez as the Gunners secured a 3-1 win against Manchester United. You can’t imagine it will be that long before he gets his first competitive appearance for the senior team.