Wilshere, 18, was a substitute in last month's friendly against Hungary and was expected to sit out the competitive action before returning for the France friendly in November. But a string of outstanding Arsenal displays have proved impossible for Capello to ignore and the teenager will now take his place in his first competitive England squad.
Capello plans to let Wilshere play for the Under 21s against Romania at Carrow Road next Friday before calling him back to the senior set-up.
Gunner be great: Jack Wilshere looks set to for a call-up to Fabio Capello's England squad
Newcastle's Andy Carroll was also omitted from the Under 21 squad, fuelling speculation that he is set for his first senior call.
Sportsmail understands that is not certain but with doubts over Wayne Rooney's fitness and the loss of injured Jermain Defoe, Carroll, 21, appears to have at least forced his way on to Capello's radar.
Rooney believes he will be fit to join the squad next week despite the claims of Manchester United boss Sir Alex Ferguson who says the striker will be out for three weeks. Rooney even thinks he could face Sunderland this weekend, having trained on Thursday following a scan on his left ankle.
It is a view shared by Sunderland boss Steve Bruce, who said: 'All this 'Is he out for three weeks?' - I don't know whether he is or whether Sir Alex is playing one of his games. I wouldn't be surprised to see him on the team sheet.'
Tall order: With fitness issues up front, Capello could hand Andy Carroll his first call
Rooney, however, is willing to stand up to Ferguson if his boss tries to stop him linking up with England. Keen to avoid a clash with Ferguson, Capello and the FA will hope United approve Rooney's inclusion in a squad that will be named on Monday.
Ferguson is trying to protect his prized asset amid concerns about his fitness and state of mind, given the current chaos in his private life.
United team-mate Ryan Giggs feels his manager is right because the attention on Rooney is massive.
Fighting to be fit: Wayne Rooney is desperate to return to action despite United saying he faced 2-3 weeks out
'The focus on players has changed,' he said. 'It's on the front pages and in the gossip magazines. The exposure is huge.'
But Giggs disagreed with Kevin Keegan, who said Rooney had to accept the situation given his decision to court media attention in the first place.
'It doesn't matter if you sell your wedding photos or not, the pressure on footballers has just got bigger,' he said. 'If he did or didn't sell his wedding photos, there would still be people following him and giving him stick. It's not a factor. But I've no concerns about his form. He is a quality player. Wayne will start scoring goals sooner rather than later.'
Capello will also be keeping tabs on Theo Walcott who might yet return for Arsenal's game at Chelsea on Sunday. It will be interesting to see if he is recalled given James Milner's suspension and Aaron Lennon's loss of form.
The England boss is considering other options because a number of forwards are struggling with injury and two others to merit consideration are Jordan Henderson and Daniel Sturridge,although both were named in the Under 21s along with Kieran Gibbs.
Capello is undecided about the captaincy, and whether he should stick with Steven Gerrard who was skipper in the absence of the injured Rio Ferdinand. Capello will not make up his mind until he meets the players next Thursday.
Ferdinand, troubled by back problems and ruled out of the World Cup because of a knee injury, recognised the problem after playing in United's 1-0 win in Valencia on Wednesday.
'I've been out such a long time that to expect me to come back and play bang, bang, bang on the bounce is perhaps unrealistic,' he admitted.
England boss Capello will not rule out injured Rooney for Montenegro clashCheer up, Wayne! Crocked United striker leaves hospital after scanCapello poised to call up Newcastle striker Carroll for Euro 2012 qualifierRosicky hails Arsenal pal Wilshere and says teenager has 'great future'