Deportivo La Coruna have cancelled the signing of winger Julio Rey after they discovered an abusive tweet he wrote about the La Liga club in 2012.
The 20-year-old, who played for fourth-tier Pobla de Mafumet last season, already had photos taken of him in Deportivo's kit.
"The club have decided to cancel the transfer after analysing an unfortunate comment on the player's social media profile," said a club statement.
"A player deserves to wear the shirt if he's an example of sportsmanship."
Rey, whose tweet contained an expletive, was set to complete his transfer over the weekend, before the club made the discovery.