With Emi Martinez soon to be gone and Rúnar Alex Rúnarsson on his way, Arsenal have maximized the financial potential from selling Martinez, and can set about buying a much needed upgrade in midfield. The potential departure of Lucas Torreira will also help raise funds. However, whether Arsenal sign Thomas Partey, Houssem Aouar, or someone else, another departure will have to happen, as right now, Arsenal have fallen afoul of the Premier League’s squad rules.
As a refresher, here are the rules:
Each Premier League team can only register 25 players over the age of 21 for that season’s first-team matches. Of those 25 players, no more than 17 can be non-Home Grown Players. In other words, if you want the full complement of 25 over-21 players, you have to have at least 8 Home Grown Players.
A Home Grown Player, as defined by the Premier League, is a player who: (a) is 21 or older on January 1 of the year in which that season begins; and (b) spent three years between the ages of 16 and 21 with a team in the English football League system.
Arsenal, then, have 18 non Homegrown players over the age of 21: Leno, Tierney, Sokratis, Gabriel, Ceballos, Lacazette, Özil, Torreira, Willian, Aubameyang, Cédric, Pépé, Mustafi, Pablo Mari, David Luiz, Elneny, Kolasinac, and Xhaka.
The number of non Homegrown players over the age of 21 is the key number—because you can only have a maximum of seventeen. Arsenal can only name six Home-Grown players over the age of 21: Bellerin, Maitland-Niles, Holding, Chambers, Martinez, and Matt Macey. Emi Martinez, so the number of players in the squad will be capped at twenty-three, and reduced to twenty-two when Martinez leaves. That, though, matters less as Arsenal have a number of key squad members under 21: Saliba, Saka, Nelson, Willock, Guendouzi, and Nketiah.
Thus, to include new goalkeeper Rúnar Alex Rúnarsson in the team, two of the current non-homegrown players will have to leave. To include a new midfielder, three of the current non-homegrown players will have to leave: three from the contingent of Sokratis, Torreira, Mesut Özil, or Sead Kolasinac.
Arsenal may have the financial flexibility from sales to buy a midfield upgrade such as Thomas Partey or Houssem Aouar. But, in order to register them as players, they will need to move on from some current senior players, or leave them out of the Premier League squad entirely.