Middlesbrough have advised AZ Alkmaar to direct their claim for compensation over their failed bid to land Afonso Alves to Heerenveen.
AZ have demanded £5.9million from the Brazilian after missing out on his signature in January despite their claims they had a pre-contract agreement with him.
However, the Teessiders, who smashed their club record transfer fee to take the 27-year-old to the Riverside Stadium, insist the latest development has nothing to do with the player.
A club spokesman said: 'We believe this is a matter between Heerenveen and AZ and that Afonso should not even be involved.'
Boro's comment came after AZ, who initially took their case to the Dutch Football Association, lodged their claim as the matter went to arbitration with the hearing resuming on May 19.
The club's lawyer, Eric Vile, said: 'We are claiming this amount of money on the basis of FIFA's rules.'
Boro finally got their man after an almighty wrangle with the Alkmaar club, who were convinced he was their player.
However, having failed to reach a conclusion in their own negotiations to land a man who had scored 34 goals in 31 matches during his first season in Holland, they saw the English club step in push home their interest.
AZ's efforts to persuade the Dutch FA to intervene came to nothing and Alves became a Boro player as the closure of the January transfer window loomed.
The South American has taken time to adapt to the Barclays Premier League, but announced his arrival in earnest with both goals in the 2-2 draw with Manchester United earlier this month.
His third for the club came in Saturday's derby clash with Sunderland, although his 73rd-minute equaliser was not enough to claim a point as the Black Cats snatched a late victory to secure their top flight status.
Boro manager Gareth Southgate will hope his big money signing can find the target against this weekend as Boro attempt to end their own relegation fears when FA Cup finalists Portsmouth visit.
They are currently four points clear of the drop zone and with Manchester City due on Teesside on the final day of the campaign, they know their fate is in their own hands.