FIFA blocked Silva after his move from Sporting CP was completed just seconds after the deadline fell.
"I have had some injuries throughout my career, but at the time I knew why I did not play, the injuries are a part of football and I always accepted that, but this whole situation was not correct, it was not correct because I was physically fit to play and I did nothing to provoke this situation," the midfielder snapped.
"I will never understand the decision of FIFA.
"There is no protection for the footballer in these situations. The footballers are the most important, right? So why does not FIFA realise this and make exceptions?"