Borussia Dortmund sporting director Michael Zorc has expressed frustration with the attitude of striker Pierre-Emerick Aubameyang, who was dropped for Sunday's 0-0 draw with Wolfsburg after missing a team meeting.
The 28-year-old was not named in Dortmund's squad because he skipped the briefing on Saturday, with coach Peter Stoger coming down hard on the striker.
Zorc spoke about the situation, revealing that the club held discussions with the reported Arsenal target earlier on Sunday.
"At some point you can't tolerate it [lack of discipline from Aubameyang] anymore," Zorc said.
"I don't know what's going on inside his head. We had a very contentious discussion today. We're not used to this behaviour from him. It can't go on like this."
Dortmund sorely missed Aubameyang's clinical finishing and wasted a host of chances in the stalemate, passing up the opportunity to go second.
But goalkeeper Roman Burki backed Stoger's decision and urged Aubameyang to get his head right so he does not miss more games as a result.
Burki told Sky Sport : "I support it. It was a logical decision.
"There are rules which apply to every player, regardless of how many goals he scores or prevents. It would be a shame if he missed out again due to his stupid actions."
Stoger expressed hope that both sides can move past the controversy and indicated Aubameyang will start with a blank slate once the new week of training begins.
"There is the opportunity to show that he is ready for him every week," Stoger said. "We assume that he will appear tomorrow for training."
Aubameyang's attitude has been the subject of several media reports in recent weeks, with one German publication claiming the striker's headline-hogging and special privileges would not be tolerated at Bayern Munich.
And Aubameyang's father — who is also the player's agent — launched an attack at the reporter who posed that theory on Sunday, after his son critcised the use of the phrase "monkey circus" in the piece.
"A s****y journalist who compares my son to a monkey," he wrote on Instagram.
"I feel like he wants to take us back to Hitler's time. I just think the little monkey [meaning Aubameyang] and his family have to leave here because it becomes unlivable. At least this small class newspaper will be at peace to know we are no longer at home here."