The Manchester United midfielder made his return to first team action with a one minute cameo, his first in 19 months, against Sunderland this month.
But his selection represents a huge gamble for Capello, who has apparently accepted his first-choice holding midfielder Gareth Barry will be absent in South Africa.
Hargreaves was one of the stars of EnglandÃ¢â‚¬â„¢s 2006 campaign, and seemed set to play in important role in CapelloÃ¢â‚¬â„¢s new England.
But injury setbacks since his Ã‚Â£17 million move to Manchester seemed to have all but scuppered his chances of making the squad, particularly as Capello has repeatedly stated he will not risk injured players for the tournament.
BarryÃ¢â‚¬â„¢s absence appears to have altered the ItalianÃ¢â‚¬â„¢s thinking however and he will have the opportunity to analyse the Canadian born playerÃ¢â‚¬â„¢s fitness before narrowing his squad.
A fully fit Hargreaves would be a huge boost to the English squad. The former Bayern Munich man is tenacious in defensive midfield and can suffocate even the most creative of attacking players.
CapelloÃ¢â‚¬â„¢s England have struggled against sides such as Spain whose midfielders can expose their rigidity between defence and midfield; an area of the field Hargreaves operates effectively in.
He is also a veteran of big match situations having won Champions League winners medals with both United and Bayern.
Hargreaves can also deputise more than capably at right-back, a position where England are weak, where his excellent crossing ability could be a bonus for a side with the likes of Peter Crouch to call on.
CapelloÃ¢â‚¬â„¢s England squads have been largely consistent in the time since his appointment but with the World Cup approaching there are signs that the Italian is prepared to be creative.
Jamie Carragher, who retired from international duty in 2007, is set to be tempted from retirement and injury ravaged Ledley King may also make the plane when it sets off to South Africa next month.
MORE: Man United latest news
MORE: Arsenal latest news
MORE: Chelsea latest news
MORE: Liverpool latest news