The England international striker missed the closing stages of the 2014-15 campaign due to the problem and Arsene Wenger revealed on Friday that the forward has not yet recovered from the injury and has not yet returned to full training.
The Frenchman is expecting the forward to be out of action for another three weeks as he looks to return to full fitness ahead of the new season.
Wenger told a news conference at Arsenal’s London Colney training ground on Friday: “Welbeck has not completely recovered, he is not in full training.
“He is supposed to start to go outside and run again this weekend and if that is positive in the next three weeks he will be available.
“He will be short for the start of the season in two weeks, but three weeks should be all right.”
Midfielder Mathieu Flamini is the only other injury doubt ahead of this weekend’s tournament.
“We have everybody available who came from Asia,” he continued. “We have no injuries.
“Flamini has a little bit of a knock on his ankle but I will decide if I involve him or not over the weekend. Apart from that I hope I can give 90 minutes to every player.”
The Arsenal boss also revealed that Alexis Sanchez is not due to report back to the club until 3 August, while David Ospina has also been granted an extended break.
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