The Manchester City midfielder was expected to be sidelined for four weeks after suffering ankle ligament damage against Tottenham at Eastlands on May 5.
However, he was included in Capello's provisional 30-man squad earlier this month and scans yesterday provided cause for optimism over the 29-year-old's fitness for South Africa.
Capello told Sky Sports Italia: "His recovery time is shorter than we thought. We are going to decide next week. We are very confident."
Manchester United striker Wayne Rooney on Tuesday played down fears he was suffering from an ankle problem after being hampered by a groin injury during the latter part of the campaign.
The Italian added: "As for Rooney, he's a very important player and he will be in South Africa. But he's not more important than the team. He's okay at the moment - he's recovered and he's 100%."