Borussia Dortmund have left Pierre-Emerick Aubameyang out of the squad for their trip to Hertha Berlin, with sporting director Michael Zorc questioning the striker's mentality amid reports he is close to joining Arsenal.
Dortmund hit out at Arsenal boss Arsene Wenger after the Frenchman suggested the Gabon international would be a good fit at Emirates Stadium during his media conference on Thursday.
Aubameyang has been strongly linked with a switch to Chinese Super League side Guangzhou Evergrande Taobao, but he is also reportedly a target for the Gunners as a replacement for Alexis Sanchez, who appears set to join Manchester United.
Zorc labelled Wenger "disrespectful" for speaking about Aubameyang and confirmed ahead of Dortmund's match against Hertha on Friday that the 28-year-old would not be included in Peter Stoger's squad.
"Auba trains in Dortmund," Zorc told reporters. "We have the impression that Aubameyang is not 100 per cent mentally focused. It's a difficult situation."
Stoger stated earlier on Thursday that Aubameyang was in contention to feature against Hertha despite ongoing rumours about his future.
"It's clear that it [transfer speculation] is exciting for everyone, but it was really not an issue for us," he said.
"If he goes with us [to Berlin], of course he could play as well, but there is no guarantee for anyone.
"Basically, he decides whether he qualifies for this team. I currently have the impression that everything is OK."
Aubameyang was left out of Stoger's squad for a 0-0 home draw with Wolfsburg last weekend after missing a team meeting.
He was also temporarily suspended by the club earlier in the campaign due to disciplinary issues, his poor time-keeping reportedly the problem.
Zorc previously said he does not feel that Aubameyang's behaviour is an attempt to force a move away from Dortmund in the same vein as Ousmane Dembele, who went on strike ahead of his club-record switch to Barcelona.
Despite an unsettled season, Aubameyang is BVB's top goalscorer in the Bundesliga with 13 goals in 15 appearances.