Former Barcelona chief Andre Cury is stunned they allowed Arthur to leave for Juventus last summer.
Arthur was sent to Juve in a swap for Miralem Pjanic.
Speaking with Sport Cury, who scouted and helped sign Arthur for Barca, declared: "It's one of the biggest aberrations I've seen in the history of football.
"Something absurd: Arthur is 23 and earns 2 million net, and you exchange him for Pjanic who is 31 and takes 6 million?"
Cury had been a South American scout and director with Barca for over a decade.
