Viktor Gyokeres is reportedly fuming with Sporting Lisbon for holding up his departure from the club this summer.
The Swedish striker is one of the most in-demand strikers in Europe after flourishing in Portugal over the past two seasons, and had expected to get a transfer to the Premier League.
Gyokeres prefers a move to Arsenal over Manchester United, but his price-tag has become a major stumbling block for any deal.
It is understood that Gyokeres believes he reached a gentleman's agreement with Sporting last summer that would see the club accept a fee in the region of €70m (£60m) including add-ons at the end of the season.