Sanchez sustained the injury during a training session ahead of the Community Shield on Sunday and Wenger admits he is unsure how long the 28-year-old will be out of action, although he believes Sanchez is likely to miss the club's first away game of the campaign against Stoke on August 19.
Sanchez will not be available," Wenger said. "He had a little abdominal strain that he caught in training on Sunday morning before he came to Wembley.
"He had a scan two days ago and he's out for a while. I don't know [how long he will be out] - two weeks, one more week. He will not be available.
"He will not play at Stoke."
Sanchez has been reportedly linked with a move away from the Emirates during the summer transfer window, with Paris Saint-Germain and Manchester City potential suitors.
Wenger insists PSG have made no approach for Sanchez and that he has held no talks with the French club's chairman, Nasser Al-Khelaifi.
It's a long time since I spoke with Nasser because he was certainly very busy to complete the transfer of Neymar," Wenger said.
"It's a long time since I spoke to him."
Asked if Paris Saint-Germain had made an approach for Sanchez, Wenger replied: "No. I think, if you read the French papers, [Kylian] Mbappe is how they will look to finish their transfer market.
