The only obvious signs of the lessons learned by Joseph Parker on Saturday after he put himself on the brink of a world heavyweight title fight were slight puffiness under his left eye and a thin red line, as if drawn by pencil, visible through his closely cropped hair above his left ear.
There will be intangible ones, though, in terms of self-belief and the knowledge that the 24-year-old has a fair bit to learn yet, that will stand him in good stead for when he eventually challenges for the IBF title.
As his trainer Kevin Barry said, this was a reality check. The important thing was that he passed it, with the judges rightfully giving him a unanimous decision over Carlos Takam, who looked in the driver's seat in the fifth round but who couldn't put his foot on the gas when it counted.
"It was his first encounter of competition from the elite level," Barry said of Parker.