South Africa [Images] captain Graeme Smith [Images] will be out of action for six weeks after he broke his left little finger on the second day of the third and final Test against Australia [Images] in Sydney on Sunday.

Smith, who was set to miss the one-day series in Australia and fly home after the third Test to inject his own blood on his injured right elbow, was surprised by a Mitchell Johnson [Images] delivery and was struck on the knuckle on his little finger.

The left-hander ran a single to complete his 30 runs before leaving the field in obvious pain. The X-rays showed a break in the fifth metacarpal and he is unlikely to bat in the second innings.

Smith returned from hospital to the dressing room later in the afternoon with his left hand in a cast.

According to South African team management, a stand-in captain will be decided before the second innings. With vice captain Ashwell Prince [Images] also out with a hand injury, wicketkeeper Mark Boucher [Images] is the leading candidate to skipper the side which is looking for a historic series whitewash of Australia.

Smith will meet with the team's medical specialists in Pretoria next week to plan his recovery from both injuries and get ready for the home Test series against Australia, which starts on February 26.

A Cricket South Africa statement said, "Medical opinion is that he will not require surgery -- the injury has been placed in a plastic cast -- and that the recovery time should be approximately six weeks, the same length of time he is likely to require to allow his elbow to recover."