Pierre-Emerick Aubameyang was dropped from Arsenal's win over Southampton after returning home from France a day later than agreed.
The Arsenal captain was given permission to go abroad on Wednesday morning to collect his sick mum and bring her back to England.
However, it had been agreed that the striker would return later that evening to ensure he would be ready to train on Thursday.
The Athletic have now stated that Aubameyang breached the agreement and flew back to North London on Thursday morning instead.
The current Covid testing protocols also meant that Aubameyang was unable to return to training until he had produced a negative PCR test.
As a result, Aubameyang was told not to report to London Colney for Arsenal’s training session on Friday and was encouraged to train at home.
Mikel Arteta also made the decision to drop the Arsenal captain for their 3-0 win over Southampton on Saturday.
Speaking after their victory on Saturday afternoon, Arteta repeatedly refused to be drawn on the incident. He said: 'Unfortunately, [Aubameyang has been left out] due to a disciplinary breach.
'I think we've been very consistent with no negotiables as a team that we have set ourselves as a club, so he's not involved today.
'Certainly, it's not an easy situation, a situation that we want our club captain to be in.'
Arteta also refused to fully answer seven press questions related to Aubameyang in the wake of the demolition of Southampton.
The Arsenal manager said: 'Let's talk about the game, guys. I try to explain to you what it was and I did it frankly and I'm not going to say anything else.
'I'm going to focus on the performance and what the team did on the pitch.'
This is not the first time Aubameyang has missed out on a game to be with his mum - who has struggled with 'health issues' this year.
Aubameyang previously missed Arsenal's 3-1 win over Southampton in January after Arteta afforded his striker compassionate leave to be with his sick mother.
Speaking at the time, Arteta said: 'It's been tough. He wants to be here, he wants to be training, he doesn't want to miss football matches.
'When you see a member of your family suffering and going through a difficult period, it drains you emotionally and you have to be close to them.'
The captain also took to social media at the time to thank his team-mates for their understanding and explain the reason for his absence.
He said: 'Hey guys, thank you so much for all the messages and calls over the last few days.
'My mother is going through some health issues and I had to be there for her. She's already much better now and I will be back home tonight. I'm more than grateful to the doctors and nurses helping her get through this.
'And of course, thanks to my Arsenal fam for the love yesterday! I'm more determined than ever to keep our momentum going!
'Thank you all again - I really am blessed to receive this level of support and love from all of you and I can't wait to be back. PEA.'