Atherton kissed his helmet discreetly and there was a brief hint of a wry grin, which was in response to Stewart's teasing as they met half- way down the pitch. "He said it was a crap shot," Atherton revealed, his 12th and most important boundary having skewed off the edge of the bat.
Afterwards, facing the ranks of a press with whom he had a sometimes frosty relationship as captain, it was clear he was not going to waste the opportunity to reflect on a day when the fates were on his side. Batsmen in mid-innings at close of play have been known to decline all interviews but, after 15 months, the chance to describe a Test century was not to be missed.
"They are all special but it has been a long time since the last one and I suppose there is a feeling of relief," he said.
"Whether the removal of the demands of captaincy had anything to do with it I cannot say but one of the reasons for my giving up the job was a lack of runs, so maybe this shows it was a good decision. I'll perhaps allow myself half a glass of champagne tonight.
"I didn't feel any different this morning. My preparation was the same as it would have been had I still been captain. I think where things are different is that over the last few weeks I have had more time to concentrate on myself, to think about my own game."
Atherton denied he had anything to prove, although he had spoken about needing to "invent a new phase" in his career. There was no better way than this for him to begin.
The day was one of frustration for South Africa, whose bowlers failed to make use of conditions favouring seam and swing and looked less of a force than had been anticipated. Nonetheless, Atherton paid them generous respect and said he had enjoyed much luck.