Du Plessis has become a hero after he hit an undefeated 110 runs in a seven-hour stint to snatch a draw for the Proteas.
"When I started working with him last year, he said he was not sure what his game plan should be in test cricket," coach Matthew Maynard told the Afrikaans daily 'Beeld'.
"My advice was to have the same intensity as in one-day cricket, in which he had fared very well, but to just reduce the risk with shots. He needed to get the bowlers to bowl to him and not chase balls outside the pen," he added.
Maynard said Du Plessis was by nature a batsman who likes to attack the bowling and feel the ball on the bat.
But there was also advice for Du Plessis from his coach, "Faf must remember that that sort of innings does not come about every day - but he certainly has shown the cricketing world that he is at home at the highest level of the game."