Apparently, Pedro Alvarez is refusing to sign the contract he agreed to with the Pirates.
More details to come.
UPDATE (9:00 PM): This is looking like a complex issue. The Players Association has filed a grievance against the commissioner’s office, claiming that the signing deadline was unfairly extended for all teams/players. Major League Baseball claims that the signings were legitimate. Due to the grievance, Alvarez is refusing to report, although the dispute would affect other players as well. The earliest potential date for an arbitration hearing is September 10. We will have to see what happens.