#7 Joel Campbell (Arsenal)
Believe it or not, Campbell is still at Arsenal. He has been with the club for seven years now, but has just returned from a sixth loan spell away from the club. He spent last year at Real Betis, but because of injuries, he only made eight appearances in La Liga, scoring two goals. He has only spent one full season at Arsenal, and that came in 2016, when he made 19 appearances, scoring three goals.
It looks like the ship has sailed at Arsenal. They already have an awful lot of attacking talent in the squad, as well as a number of younger players coming through, whose progress may be slowed by keeping Campbell in the squad. He has had much greater success on the international scene, where he has been a mainstay in the Costa Rica side, playing 79 games for his national side, scoring 15 goals.