Smith out for six weeks after fracturing left hand

South Africa's chances of claiming a 3-0 victory over Australia may have fractured with Graeme Smith's left hand. Smith became the first victim of a cracking pitch when a Mitchell Johnson delivery surprised the captain, cutting back and striking the knuckle on his little finger.

After being examined on the ground, Smith retired hurt on 30 and went for x-rays that showed the break in the fifth metacarpal. He returned to the dressing room with a plastic cast on his hand and will be out for the next six weeks.

Normally the injury would be a serious concern for the South Africans, but Smith already planned to miss the upcoming one-day series due to his right elbow problem. He will meet with the team's medical specialists in Pretoria next week to plan his recovery from both injuries. In the lead-up to the Test he spoke of having his own blood injected into the tear in his arm and is confident of being ready for Australia's Test tour in February.

Smith will bat only if South Africa need a handful of runs for victory and a stand-in captain will be decided before the second innings. With Ashwell Prince also out with a hand injury, wicketkeeper Mark Boucher is the leading candidate.

"If we need 10 to win I'm pretty sure Graeme will go in there, but it all depends on the situation," the spinner Paul Harris said. "He's disappointed to be injured, but this is the kick he needed to take a little bit of rest.

"The big guy has been playing for a long time in a lot of pain. I don't think people realise how hard it is to play in the pain he is in. A lot of other guys would have packed in a long time ago."

When Smith was hit by Johnson, the team physiotherapist Shane Jabbar returned to the field shortly after treating the batsman's elbow. He knew he had to retire hurt when he was unable to put his glove back on.

The sunny weather in Sydney will widen the cracks on the pitch and the visitors will have to bat last when the surface is at its most testing. Whether South Africa are pushing for victory or attempting to hold on for a draw on the final day, their situation will become tougher without Smith, who has 323 runs in the series.

When Smith was batting, he was able to push South Africa forward while Neil McKenzie's struggles for fluency continued. Smith was fortunate to survive an edge behind on 18, with the wicketkeeper Brad Haddin not going for a ball which bounced short of Matthew Hayden at first slip. The next offering from Doug Bollinger was pulled for four and there were another four boundaries during his 31 deliveries.

South Africa reached 1 for 125 at stumps in reply to Australia's 445 and Harris was sure of their ability to match the total. "We're pretty confident that we can post close to their score, maybe a touch more," he said.

Despite Smith's injury and the team being behind by 320 with three days remaining, Harris said they would not be sitting back to defend their 2-0 lead. "We play every Test to win, it's the South African way," he said. "We never play a Test to draw."

Harris collected 3 for 84 for the innings while Dale Steyn captured 3 for 95. Steyn has a bruised left heel and delivered only six overs on the second day, but will bowl in the second innings.