Australia's Mitchell Starc has been cleared of serious injury ahead of day two of the Boxing Day test after suffering a finger injury on day one.

The fast bowler left the field and was sent for an X-ray after the conclusion of the day's play, now cleared of any serious injury and set to join his teammates as day two begins.

Cricket Australia reported that despite the vision seen of the injury, Starc did not suffer a dislocation and the injury was not as serious as first thought.

Speaking after the conclusion of day one, teammate Nathan Lyon admitted that Starc's injury didn't look great.

โ€œNot ideal, I don't think,โ€ Lyon said to cricket.com.au

โ€œHe's popped off for a scan now. Fingers crossed we can get the best possible result with his scan.

โ€œI donโ€˜t know what he's technically done, but it doesn't look the greatest.

โ€œHe went out the back and tried to bowl, but I think it (felt) a bit different to be honest.

โ€œUnfortunately, injuries are part of the game โ€ฆ all we can hope for is he gets the best possible result with the scan โ€“ heโ€˜s there as we speak.โ€

Australia head into day two after a strong Boxing Day performance, bowling out South Africa for 189. Theyย will resume day two at 1/45.