The row between Sporting CP and West Ham over William Carvalho could escalate into legal action, if tweets apparently posted by the son of Hammers co-owner David Sullivan are to be believed.
Sullivan Sr last week claimed West Ham initially had a club-record bid for Carvalho rejected and then accepted on deadline day, but without enough time left to complete a deal.
Sporting's communications director Nuno Saraiva angrily rejected that suggestion, publishing a statement on Facebook accusing Sullivan of lying and calling on him to provide proof that an offer was both submitted by the Hammers and received by the Primeira Liga side.
West Ham have not formally responded to those remarks.
But posts appearing on an unverified Twitter account, seemingly belonging to Sullivan's son, David Sullivan Jnr, suggest the Hammers may not be willing to back down.
The tweets read: "West Ham are commencing legal proceedings against the communications director of sporting Lisbon as a written offer for the player was made… To Bruno de Carvalho the president of sporting Lisbon. To say we never made an offer is nonsense and serious libel."
West Ham are commencing legal proceedings against the communications director of sporting Lisbon as a written offer for the player was madeSeptember 3, 2017
To Bruno de Carvalho the president of sporting Lisbon. To say we never made an offer is nonsense and serious libelSeptember 3, 2017
It remains to be seen if Sullivan Jnr can be deemed an authoritative source on the inner workings at the club.
His brother Jack Sullivan, managing director of West Ham United Ladies and seemingly privy to inside information thanks to his father, has often provided updates on West Ham's transfer dealings.
The most notable social media activity of David Sullivan Jnr's to date, though, saw him issue an apology for criticising players on Twitter in 2015.
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