Wenger insisted Sanchez did not refuse to play in Sunday's 2-1 Premier League defeat at Bournemouth, though the Chile striker did not travel to the south coast.
Wenger believes Sanchez could even yet still stay at Arsenal, even though he has refused to sign a new contract, with his current deal expiring in the summer.
Wenger confirmed he has received assurances from Arsenal's board that Sanchez will be replaced if he leaves, with Manchester United appearing ready to pip Manchester City to the 29-year-old's signature.
"Alexis would have played," said Wenger, after Arsenal leaked two goals in five minutes to slip to defeat. Alexis would have played, but it's a difficult period for him.
"He's always been committed until now but he could have gone yesterday and he could go in the next 48 hours. It was difficult for him because he was on standby. That's why I decided not to do it. He did not refuse to play."