Wilshere has not featured for the Gunners at all this term after suffering an ankle injury during pre-season.
The England midfielder underwent successful surgery but then suffered a stress fracture during his rehabilitation in January.
The 20-year-old was recently ruled out of Euro 2012 – and Wenger is refusing to confirm whether the midfielder could be fit to play for Team GB at the London Olympics.
“I do not want to set the Olympics as a target because I do not know whether Jack will be fit to start at the beginning of the season,” said the Arsenal boss.
“When we start pre-season training on 9 July, if he can join in, then we have won the battle, but that is not guaranteed.
“You get the first knock, but think: ‘OK, at least I will be ready for the Euros.’ Then you have to convince him: ‘Look my friend, it will not work for the Euros.’ You knock him down again.
“Then you set him another target – the Olympics. But if he doesn’t make it, he will lose a complete appetite for rehab because it’s difficult.
“Let’s take our time and not set any specific targets.
“The most important thing for him is to focus on day-to-day work and see if he can get better.”
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