Arias has moved to the Spanish capital from Eredivisie champions PSV Eindhoven, with the Dutch club offering thanks for his years of service:
However, not everybody agreed with the decision to let Vrsaljko move on:
Simon Harrison @simonhfootball
As rumoured for a long while, Santiago Arias comes in, with Sime Vrsaljko departing on loan. There has to be something below the surface with Vrsaljko, he firstly struggled to get games for no good reason and then gets moved on when his stock is high. https://t.co/7WvXad7r1J
The exchange of right-backs could favour Atletico after Arias scored four goals and provided six assists in all competitions during his final year with the Rood-witten. By contrast, Vrsaljko didn't get on the scoresheet, but he did provide four assists to help Madrid win the UEFA Europa League.
Sealing a move to La Liga caps a difficult summer for Arias:
Despite any reservations about the 26-year-old, Atleti may have beaten some strong competition for the South American. Calciomercato's Kaustubh Pandey recently reported Serie A outfit Napoli had agreed a fee with PSV.
If Simeone's expertise defensively can iron out the deficiencies present in Arias' game, this will prove another shrewd signing for a manager who is carefully retooling his squad to get closer to champions Barcelona.