For a period of time, Arsenal have been among the biggest net spenders in the Premier League. The Gunners have often spent big on players but brought in far smaller sums on player exits. That has changed, somewhat, in recent years with the big-money moves of Emile Smith Rowe, Folarin Balogun and Eddie Nketiah. And smart sell-on clauses such as the Biereth one are shrewd moves as well.