Cape Town - Australia's interim coach Troy Cooley has fired the first punch on the psychological front ahead of their tour to South Africa.Cooley fired the first - albeit a very cautious - blow towards the Proteas by labelling their batsmen as a "bit on the old side".The Australians tackle the Proteas from October 13 in two T20 internationals, three ODI's and two Test matches.The South Africans last played a Test match in January against India and according to the Beeld newspaper, five SA batsmen from that top order are already 30 years or older - Graeme Smith (30), Alviro Petersen (31), Jacques Kallis (35), Ashwell Prince (34) and Mark Boucher (34)."They've got a great bowling line-up and their batsmen, even though they're a little bit older, they're still producing the runs," Cooley told the website, ESPNcricinfo."They sit well above us on the Test table and we'll be working very hard to chase them down." The Proteas - with 118 points - currently occupy second spot on the ICC Test rankings - seven behind England on 125. The Aussies are 14 points behind South Africa.South Africa received a setback on Wednesday when their limited overs captain, AB de Villiers, fractured his left hand while practicing with the Royal Challengers Bangalore in the Champions League T20 in India. He will undergo surgery on Friday and is expected to be out for four to six weeks, ruling him out of the limited overs leg of the Australian tour.