Arsenal’s woes were compounded after they were annihilated by German side Bayern Munich yesterday.
Chilean playmaker Sanchez returned to the Arsenal starting line-up on Tuesday evening against Bayern Munich after starting from the bench in the 3-1 defeat at Anfield.
Arsenal legend Pires says Sanchez left training last week following a poor tackle from a team-mate rather than an incident with Gunners boss Wenger.
Pires, who has been working at his former club this season, told beIN Sports: ‘I was there. There was a bad tackle on Alexis Sanchez, a clash, he left the pitch.
‘Fans have to understand. There was a disciplinary sanction. Nothing serious happened. I was there yesterday too, [there was] no problem.’
When asked about the reported bust-up with Sanchez, Wenger said earlier in the week: ‘I am not aware. Nothing happened. Nothing at all.’
Pushed on his current relationship with the 28-year-old, who has emerged as a target for Chelsea and Manchester City, Wenger added: ‘Honest and normal like with every single player.’