Renshaw's dream Test continues with first wicket to put Aussies on top

Fourth-innings specialist Aiden Markram remains unbeaten on 45 off 115 and he has an able offsider in Wiaan Mulder (5*). Australia is absolutely on top of South Africa but the players look steely-eyed as they walk off, knowing they have a lot of work to do on day five. "It's a grind so hopefully a few cracks open up," Josh Hazlewood tells ABC Sport. "It's pretty good a bit of rough for the spinners an a bit of tail with the old ball."