That's all from us on behalf of Cricinfo today. On behalf of Alex from Australia and M Venkat Raghav from India, this is Sreshth Shah saying bye-bye!

5.31pm We'll head into day five with the visitors holding all the aces. Here's a recap of the day:

Australia are firmly in control of the Durban Test, with South Africa finishing day four on 102 for 4 in pursuit of an imposing 421. Matt Renshaw followed his first-innings 190 with a fluent 82 off 99 balls as Australia raced to 314 for 6 declared, scoring at 5.41 an over. Nic Maddinson set the tone with a 38-ball 48, while Pat Cummins provided the late fireworks with an unbeaten 32 off 12 balls, including three sixes in an over off Simon Harmer. The declaration came by tea, leaving Australia's bowlers enough time to make significant inroads.

And they did just that. Josh Hazlewood removed Ryan Rickelton with a vicious bouncer before trapping David Bedingham lbw for 46, extending the curious run of no batter other than Renshaw reaching fifty in this Test. Temba Bavuma and Tristan Stubbs managed just one each, with Renshaw dismissing the South African captain for his maiden Test wicket, courtesy of a bat-pad catch taken by Maddinson. Cummins then produced a beauty to find Stubbs' outside edge. Markram went into survival mode after Bedingham's dismissal, and alongside an equally watchful Wiaan Mulder, ensured South Africa suffered no further damage. Markram finished unbeaten on 45 off 115 balls, with Mulder on 5 off 23.

It was a marathon day of cricket, a rarity in modern Test cricket, particularly outside Asia, with the heavy use of spin helping the teams make up for time lost to bad light over the first three days. But the surface is increasingly playing tricks, with variable bounce and significant turn making batting a challenge. South Africa still need 319 runs with six wickets in hand, and with drier weather forecast for the final day, Australia will fancy their chances of wrapping up a victory. South Africa, meanwhile, have an entire day to survive.

The clock has ticked over to 5.30pm. So should be the last ball of the day

Stefan: "Is this 2018 v2.0? Valiant Markram century in an unsuccessful Durban chase, followed by a fightback at St George's, before all hell breaks loose at Newlands? " -- tantalising

Oishik : "Quite an odd thing to note but bedingham's first class strike rate and test strike rate is 67. And his innings strike rate in both the innings was 67. That's a striking detail. -- Sorry, you lost me at 6-7

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