Du Plessis said: 'After that first Test match, the guys were really motivated to turn it around.
The final wicket came when Nathan Lyon was run out off the bowling of Morne Morkel, who passed 300 Test wickets during the series and was playing his last match before retiring from global cricket.
Captain Tim Paine said Australia must improve their "behaviour" after they were thumped by 492 runs by South Africa in the fourth Test to lose the controversial four-match series 3-1.
The ball-tampering scandal has changed plenty of lives and generated huge debate about the team's conduct, which new captain Paine has already changed.
"It is going to be a different style than a lot of the guys are used to, but I think we will find it pretty quickly".
South Africa also handled the pressure moments better than their visitors, though Du Plessis admits the controversy from one test to the next took its toll.
No Australian batsman scored a century this series.
South Africa had failed in seven home series against Australia since being welcomed back in 1991 to global cricket.
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The home side emphatically won the series 3-1 after losing the first Test in Durban. "We nearly went from motivated to motivated/angry to try and turn it around". No Australian made a hundred.
South Africa has been formidable in their own den.
The lanky paceman went past 300 Test wickets during the third Test at Newlands and played through the pain to snap up two wickets in the final innings as Australia were thrashed by 492 runs.
Markram finished the leading run-scorer of the series, tallying 480 runs at 60.
While South Africa were eventually bowled out for 298, Markram's 143 proved to be the foundation for a successful series on a personal level - he would later post 81 in Cape Town and 152 in Johannesburg.
Rabada picked up 5/96 in the first innings, which included the wickets of Cameron Bancroft, Steve Smith and Shaun Marsh, and went on to credit six more to his account in the second (6/54) - David Warner, Usman Khawaja, Shaun Marsh and Mitchell Marsh being four of his victims - and helped restrict South Africa's target in the fourth innings to 101, which they achieved with six wickets in hand.
The 33-year-old Morkel, who made his worldwide debut in 2006, says he will miss playing front of the South African public but is happy to pass the torch onto another young player.
"There was not one day did I not enjoy coming to nets. I still have a love of the game".