Adelaide - Faf du Plessis, motivated by the events of his controversial ball-tampering case, ranked his unbeaten century in South Africa's pink-ball Test with Australia on Thursday as the best of his career.
The Proteas skipper hit an unbeaten 118 and then caught the Australians off-guard with a surprise declaration at 259 for nine to have the tourists in a good position at the end of the opening day of the third Adelaide Test.
Australia, who were unable to use David Warner to open the innings over the time he sought off-field treatment, got to stumps at 14 without loss.
It had been a tumultuous few days for du Plessis, who was found guilty of ball-tampering by the International Cricket Council after he was caught on camera sucking a mint and rubbing saliva into the ball during last week's second Test against Australia in Hobart.
Given all the drama from his much-publicised appearance at the hearing it was a remarkable effort of concentration and will for du Plessis to conquer the Australian bowlers and post his sixth Test century, one he rates as his best.
"My best. Everything. What was required to get to this point now. Surprisingly, technically, I was the best this whole series. I felt really good, but in the context of everything else, (it was) the best," he told reporters.
"I was really motivated. I felt it needed a character test, and the only way I could do it was by scoring runs."
But du Plessis, who was booed by the home crowd as he came out to bat with his team wobbling at 44 for three, was dismayed by yet more booing when he reached his courageous century off 147 balls.
"I was expecting a little bit of hostility, but not to that extent," he admitted.
"When I came out to bat I was obviously quite aware of it and as the innings went on it disappeared a bit.
"But to be really honest when I got to 100 I wasn't expecting to still get booed, so that was pretty disappointing."
Du Plessis also revealed how he had caught the Australians napping with his daring declaration late in the day, leaving the home side to negotiate the remaining 12 overs without their most experienced player Warner.
Warner had just returned to the field after seeking treatment off the field on an injured shoulder.
Under cricket's rules, a player must be on the field for the same time they spent off it before being able to bowl or bat again - in Warner's case, he was caught short.
"I listened to the conversation he had with the umpires - one ear talking to the batter, one ear listening to him," du Plessis told reporters.
"And then I heard he had six minutes left before he could bat again so I thought 'let's have a crack'."
Du Plessis showed his captaincy smarts by upsetting the Australian team's plans as they had to reshuffle their opening pair with Usman Khawaja having to join Test debutant Matt Renshaw at a testing period to stumps.
"It was just for me to take them a little bit out of their comfort zone and put someone else to open the batting," he said.