Atletico Madrid are said to have been left furious over the transfer of Thomas Partey on deadline day.
The Gunners wrapped up the signing of the Ghanaian midfielder just minutes before the deadline on a £45million deal having pursued him throughout the summer.
But Partey's now former club are far from pleased with how things panned out on the last day of the transfer window, despite being 'resigned' to the midfielder's exit.
That's because, according to ESPN, they weren't told about the move until 11.28PM Spanish time, just 32 minutes before the midnight deadline.
And by that time, the paperwork was done for Partey to become an Arsenal player.
La Liga requires all of its players to have a release clause which is handled by the league itself.
Clubs can still negotiate on deals but when it's a case of activating the release clause, as Arsenal did, it all goes through the league and there is very little Atletico could do about it.
Atletico have been left furious because they weren't told Arsenal were in talks with La Liga over activating the clause until it was too late.
They claim the delay took away crucial time they could have used to find a replacement for Partey in the dying moments of the window.
Though, that's none of Arsenal's concern, the Gunners well within their rights to get the deal done right up until the deadline.
