Characterising himself as an old but reliable piece of farm machinery, Springboks lock Bakkies Botha has announced a seemingly miraculous recovery from injury at the Rugby World Cup with the words: "I'm back!"

Only days ago the future of the combative 75-Test veteran at this World Cup seemed deeply uncertain.

South Africa team doctor Craig Roberts said Botha's chronic Achilles tendon injury was not responding to treatment "as we had anticipated."

And when his long-time locking partner Victor Matfield joined the Springboks' injured list with a hamstring strain, coach Peter de Villiers said he may have to consider calling a replacement "sooner rather than later."

But Botha has recovered sufficiently to be named in the Springboks team to meet Fiji in their second Pool D match on Saturday.

"Definitely I'll still feel a little bit of stiffness but it's like old farm vehicles in the morning," Botha said.

"It smokes a bit when you drive it around for half an hour then it's hot and it will go. So hopefully everything will run smoothly for me.

"I'll definitely start to warm up much earlier than the normal prelude. But I'm just happy to be involved with the guys to take on Fiji this weekend."

Botha was hard-pressed to explain the sudden reversal in his own prognosis. He was prevented from training for most of the first week after the Springboks' arrival in New Zealand and still trained gingerly on Tuesday.

But, he said, he was confident he would be able to get through Saturday's match without further problems.

"I trained hard last week. On the rehabilitating side and the medical side there's been a lot of work on my left achilles," he said.

"I just gave it a go on Tuesday morning and I was just happy to get through the training session, so I'm back and I'm quite happy where I am.

"As long as I just get out on the pitch this weekend and see how it goes.

"Definitely it was an amazing recovery by myself, a lot of prayers and everything, but definitely I'm happy to be on the pitch this weekend against Fiji."

South African players have commented repeatedly this week on the athleticism of the Fiji players and the different challenge they are likely to pose than Wales, who the Springboks beat 17-16 in their opening match last Sunday.

Hooker Bismarck du Plessis said that the Fijians, from one to 15 "can outrun most of our players."

Botha said he had not intention of trying to match the athleticism of his rival locks.

"Ach, no," he said. "I saw the way their No. 4 went down the touchline against Namibia and stepped inside and popped it for the centre or the wing."

Fiji coach Sam Domoni has kept an unchanged backline but adjusted his forward pack, naming Sakiusa Matadigo at No.8 in place of Netani Talei and Akapusi Qera on the openside flank ahead of Mala Ravulo.

Sunia Koto will start at hooker in place of Viliame Veikoso.

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