Australia's bowlers restore order but batting headaches remain ahead of South Africa tour

MELBOURNE, Aug 24 : Normal service resumed for Australia as their formidable bowling unit hit their marks in the second test against Bangladesh in Mackay but questions remain over a batting order that continues to misfire at the top.Australia's innings and 51-run victory was a strong comeback from the Darwin defeat as pace leaders Mitchell Starc and Pat Cummins blasted away the tourists' batters in a timely reminder of their quality ahead of a tough, three-test tour of South Africa in October.Australia's batting has left selectors with a headache, though, and struggling number three Marnus Labuschagne may be nervous about his place in the squad for South Africa.South Africa-born Labuschagne was already under major scrutiny after two poor dismissals in Darwin before he was bowled for four i