KV Mechelen have carried out their threat to challenge the circumstances behind Michael Verrips' move to Sheffield United.

The Sheffield Star says FIFA confirmed they are receipt of a complaint from the Belgian club after being contacted by The Star last night.

Verrips joined United on a free transfer earlier this summer, claiming his contract at the AFAS-stadion Achter de Kazerne had been rendered null and void when Mechelen were removed from the Europa League following a match-fixing investigation.

Although they are understood to have no issue with United, Verrips' former employers say the goalkeeper "unilaterally broke his agreement" before being unveiled by Chris Wilder's side.

"We can confirm that FIFA has received a claim lodged by the Belgian club against the player Michael Verrips, which is currently being analysed by FIFA," a spokesperson for the organisation said.