Atletico Madrid say they will not enter into negotiations with Barcelona for striker Julian Alvarez, who is considering a move to Arsenal.
Alvarez did not train on Wednesday and Thursday because of illness after a poor night's sleep on Tuesday, not because of anything related to his future.
The 26-year-old wants to join Barca, who again went public with their desire to sign him on Wednesday in an interview with president Joan Laporta.
However, Atletico have now publicly said they won't engage with Barcelona over a transfer for Alvarez.
Atletico Madrid chief executive Miguel Angel Gil told Movistar on Thursday: "My personal dream is for Julian Alvarez to stay at Atleti.
"If he wants to leave the club, we will look for an alternative, but he will never, ever, ever go to Barcelona.
"Julian is in poor health. There are people who have taken it upon themselves to deceive and confuse him, and he is going through a difficult situation.
"We are outraged and repulsed by this lack of ethics. We are not going to negotiate with Barcelona. The only firm decision is that we will not negotiate."
Gil's comments came after a club statement earlier in the day criticised Barca's behaviour around Alvarez.
It read: "Atletico de Madrid is open to standard transfer market negotiations when conducted in a professional, ethical and respectful manner.
"We fully stand behind the club's previously communicated position that FC Barcelona failed to meet these requirements and, as a result, there will not be any negotiation, and there is zero consideration of an Alvarez transfer to Barcelona."
Marca, Spain's biggest sports newspaper, had previously received on-the-record quotes from the club saying: "The player is being portrayed as the victim, but we are the only victims in this case.
"[Barcelona] have harmed us both financially and socially. There is a zero-per-cent chance of selling him to Barcelona - it's not about money, it's about dignity."
Arsenal boss Mikel Arteta refused to be directly drawn on their interest in the former Manchester City forward.
But when asked on Thursday if the club's links with the striker could be troubling some of his players, he replied: "Very simple. Whatever you read, if you have a question, come and knock on my door, and I will tell you whether it is true or not.
"Because a player in any position, if they read it, we could put a catalogue on the walls about all the players that we wanted in the last three months, and we would need the whole building.
"They know that there's so much speculation. So if ever they feel the doubt of what we think about them, and if we're going to recruit a player, I tell them straight away.
"And if we're going to sign somebody in their position, I normally tell them. I say: 'These are the plans and the reasons. We still believe in you, but the competition is going to increase'. I prefer to do it that way."
As far as Arsenal are concerned, nothing has changed. They still believe signing Alvarez is very unlikely before the deadline and would need strong encouragement from the player to start negotiations with Atletico.
There is ongoing dialogue between Arsenal sporting director Andrea Berta and Atletico CEO Miguel Angel Gil Marin, but this has been the case all summer. They used to work together at Atletico Madrid and remain close.
Atletico are already making contingency plans and are exploring the possibility of bringing in a new striker. Interestingly, one of the players on their radar is Arsenal's Viktor Gyokeres, with the Spanish club keen to gauge how open Arsenal would be to selling the Sweden international.
They were also keen on Nicolas Jackson, but he is heading to Aston Villa.
The next 24 to 48 hours have been described as crucial to understanding Alvarez's wishes: whether to stay at Atletico and regain his position among the fans and the club, or to push for an exit. Atletico do not want the situation to drag on until the final day of the window.
The situation around Alvarez's future has become "extremely tense", according to Atletico expert and journalist Ruben Uria.
Alvarez's public desire to leave has made him so unpopular with the club's supporters that they booed him off the pitch after their 2-2 draw with Villarreal on Sunday and he is understood to be starting to consider whether a potential move to Arsenal would be right for him.
Uria now believes the striker has two options. He said: "My interpretation of the statement is that Atletico is making it public that it will not negotiate with Barcelona under any circumstances, and that this is not only the CEO's position, but also that of the club and, above all, its majority shareholder, Apollo, one of the largest private equity funds in the world.
"Absolute support. It's a clear message for Julian: 'Either you go to London, or you stay. We will never negotiate with Barcelona.' It's very clear, Julian decides. London or staying in Madrid."
South American football expert Tim Vickery speaking on Your Site News:
"It is up to Atletico. They have two options: do they want to keep a player who doesn't want to be there? Or do they want to cash in?
"Clearly, they wouldn't sell to Barcelona and wouldn't sell to Real Madrid if they were interested. That does not leave them with many options; who else could afford him?
"The other options are in the Premier League. I'm not sure he was wildly happy during his time in England. He has got himself in a place where there are not many options.
"Arsenal would give a fantastic narrative. Why not try to be part of the first Champions League at Arsenal?
"Why not be a part of that? And, depending on the terms of the contract, Arsenal could be a stepping stone to Barcelona. But it is up to Atletico.
"I am told that the fans would probably take him back if he has to go back to Atletico. He is a wonderful player, a striker with the soul of a midfielder."
