Left-arm spinner Boje, the only frontline slow bowler in the squad, had his thyroid gland removed 11 days ago.

"We're still working with him, it's a day-by-day process," the South Africa team's physiotherapist, Shane Jabaar, told Reuters on Tuesday.

"I can't say we're confident he will be fit, but we will make a decision in two days' time."

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South Africa also have several other fitness worries, most notably over captain Graeme Smith, who along with Zander de Bruyn and Andrew Hall was struggling with a stomach bug.

Jabaar said Smith was "80 percent right", and that De Bruyn's condition had improved significantly.

However Hall's health remained a concern.

Jabaar said Boeta Dippenaar was still suffering the effects of a viral infection he contracted on South Africa's tour to India.

Jacques Rudolph sustained a bruised leg while batting in the nets this week and wicketkeeper Thami Tsolekile had a throat infection, although Jabaar said both would be available.