FIFA is investigating the transfer of midfielder Bruno Fernandes from Portugal’s Sporting Lisbon to Manchester United following a complaint from his former team Sampdoria, soccer’s world governing body has said.

The 25-year-old joined United from Sporting in January for an initial fee of 55 million euros ($59.39 million) and has registered three goals and four assists in nine games.

Sky Sports reported that Italy’s Sampdoria inserted a 10% sell-on clause on any profit Sporting made on Fernandes when they sold him in 2017.

However, the Portuguese club say that clause is null and void as the playmaker signed a fresh deal in June 2018 after terminating the original one.

“We can confirm that on April 3 the Italian club Sampdoria lodged a claim with FIFA against the Portuguese club Sporting Clube de Portugal related to financial obligations set out in the contract corresponding to the transfer of … Fernandes,” FIFA said in a statement released to British media.

Fernandes was one of a number of players who terminated their contracts at Sporting after a group of some 50 masked men attacked players and staff at the club’s training complex in 2018. He later decided to remain with the club.