Arsenal insist they are not responsible for the breakdown of the deal that would have seen William Saliba rejoin St Etienne on a season-long loan on Deadline Day.
The two clubs reached an agreement on Monday for the 19-year-old defender to return to the Ligue 1 club on loan for a second successive season, after he made a permanent switch to the Gunners in a £27m deal last summer.
St Etienne claim they agreed a Deadline Day deal for Saliba to return and spend a second successive season on loan but Arsenal could not finalise the paperwork ahead of the deadline.
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"Long before the transfer window closed, AS Saint-Étienne had reached an agreement with William Saliba and accepted Arsenal's offer for a season-long loan," a club statement said on Tuesday morning.
"Unfortunately, all the administrative conditions could not be met in time, in England, for the finalization of the file.
"There is a great disappointment for ASSE and William Saliba, who was particularly determined to return to the club where he had flourished."
However, Arsenal have distanced themselves from the claims and believe they did everything they were required to do, and in good time.
The north London club believe the deal was ready to be finalised, and as the receiving club, St Etienne were required to submit registration details first - but never did.
Mikel Arteta's side went on to secure the signing of Thomas Partey on a four-year deal after triggering the £45m release clause of the former Atletico Madrid midfielder on Monday.
'A surprise Deadline Day' at the Emirates
Sky Sports News reporter Dharmesh Sheth:
"It was a bit of a surprise with Arsenal. We didn't think at the beginning of the day they would get the midfielder they wanted, there was a lot of talk about Houssem Aouar in the last 48 hours, and then the one they were interested in from the very beginning, Thomas Partey, they knew they had to meet that £45m release clause, got triggered.
"They didn't have to deal with Atletico Madrid at all because how the release clause works is you go to La Liga's headquarters and put the money down. I'm not sure it was cash, I think it may have been just a cheque! Then you can talk to the player. They've got it done in quick time because it was a race against time for Arsenal to try to get this one done.
"It doesn't look like there was a deal sheet required for this, we've been told he will wear the No 18 shirt, Thomas Partey, he's joined on a long-term contract."
Deadline Day has passed - but that doesn't mean transfer business is over for Premier League clubs. They can still deal with EFL clubs until October 16. So which players could be on the move before that domestic window closing?
The extended opportunity for transfers, allowing Premier League clubs to buy, sell and loan players with clubs from the Championship, League One and League Two, offers top-flight clubs the chance to boost their squads.
Here, we pick out the players who could beat that second deadline to move to the Premier League...