Athletic Club boss Valverde believes Arteta is ‘one of the best coaches in the world’ – and says new Arsenal star is ‘already shining’

Athletic Club manager Ernesto Valverde has praised Arsenal's Mikel Arteta, calling him 'one of the best coaches in the world.' Valverde also commended a new Arsenal signing who is 'already shining' for the club, though the specific player is not named in the provided content.