“It is a strategy as old as it is effective. No longer have use for a first-team player and want to see him leave? Instruct them to train with the under-23s and let the nature of football take its course. The problem, more often than not, will soon resolve itself with a separation. This common practice has been seen across the Premier League and English Football League again this summer. Dozens of faces that no longer fit have been marginalised and demoted to train at a level that ought to be beneath them or, in some cases, all alone. …”
The Athletic