Siddle believes superior depth in fast bowling gives OZ the edge over Proteas

Pacer Peter Siddle has said that Australia has an advantage over South Africa due to their superior depth in fast bowling, and a mandate to bowl at full intensity all of the time.

The series is expected to be a duel between the two best pace attacks in world cricket as the fact bowlers from the two teams occupy five of the top eight positions on the ICC's Test bowling rankings.

Siddle said he and fellow Australian pacemen Mitchell Johnson and Ryan Harris could not afford to get complacent because of the likes of James Pattinson and Jackson Bird waiting for an opportunity in this Test series, with Nathan Coulter-Nile and Doug Bollinger just behind in the pecking order.

Mitchell Starc and Pat Cummins are also set to return to first-class cricket after injury, The Sydney Morning Herald reports.

Siddle said that depth is amazing and is probably one thing that sets Australia apart from the other bowling units in the world.

Australian coach Darren Lehmann said he had noted Siddle's inability to hold his form throughout a long series, but argued it was more of an issue during the unsuccessful series in England than the triumphant home series.

He said Siddle has been excellent for Australia over the past couple of years.