New Orleans Saints star Jimmy Graham could have cost himself $5.3m (£3.1m), thanks to the words written in his own Twitter bio.
The Saints have designated Graham as their franchise player for 2014, although there is an ongoing dispute as to whether he is a tight end or a wide receiver.
While his team insist he is a tight end, Graham is often lined up as a wideout during offensive plays, and he argues that as a franchised player, he should be due wide receiver wages.
He has filed a grievance against the ruling in order to try to get his franchise-tag salary raised.
However, despite the NFL Players Association providing evidence that Graham plays out of position 67% of the time, the NFL wants to use his personal bio against him to prove that he is in fact a tight end.
Graham's bio reads: "New Orleans Saints Tight End #80. Private Pilot."
The league's argument is that if Graham lists himself as a tight end on a personal account, he can have no complaints about being paid the appropriate wages for that position.
A decision on the matter is expected to be made in the coming days.
