Think of the first half-dozen or so words used to describe Ben Stokes. Brutal might be there. Talented, certainly. Maybe furious, committed, athletic, ginger, tattooed and, so long as you're out of earshot, balding.
But mature? That's not a word we have heard to described Stokes so often.
Yet it was Stokes' maturity that was the key factor in his fifth and perhaps most complete Test century. It was Stokes' maturity that took England from a precarious 120 for 4 (and then 183 for 5) to a final total that may well prove to be match defining. And it was Stokes' maturity that has set the example for the way England should bat in Test cricket.
That is not entirely fair. It was Stokes' maturity and Alastair Cook's excellence. Had Cook not helped England through the early onslaught - the new ball is especially tough to deal with on this pitch - it is entirely possible they could have suffered a similar fate to that experienced at Trent Bridge.
Cook and Stokes' batting isn't often compared. But there were similarities here. Both men respected the bowling, accepted that it would be necessary to proceed with caution and were prepared to soak up long periods of pressure.
So while a highlights package might feature all the familiar Stokes strokes - the crunching drives, dismissive pulls and the trio of slog-sweeps that took him past his century - it was the periods of scorelessness in between that were just as relevant. He earned the right to those boundary balls.
Most of Stokes' other Test centuries have been pretty simple affairs. Most of them have seen him simply take on the bowling and thrash his way to a century. Think of that maiden hundred made in a hopeless cause in Perth, the quickest-ever made in a Test at Lord's when counterattacking against New Zealand, or the massacre that was his double-century in Cape Town.
This wasn't like that. It was a far more measured affair. And, while there were periods when the runs came quickly - each half-century occupied 72 balls - there were also periods, such as when it took him 60 deliveries to move from 50 to 76, when he had to demonstrate those more prosaic skills: patience; discipline and an ability to adapt to the conditions and the match situation. Where once Stokes' innings were characterised almost entirely by boundaries, he now runs his singles and twos with the greed of the professional batsmen.
It was just what England needed from their new vice-captain. And it was exactly what they talked about after the debacle of Trent Bridge. It showed all the skill we've seen before, but saw it complemented by restraint and responsibility. To score runs in conditions when few others can manage it is the hallmark of the better batsmen. Nobody else on the day scored more than Jonny Bairstow's 36.
"It's the one I've had to work hardest for," Stokes said. "I came off the field after the first day and did not feel in the best of form. I had played and missed at a few balls and Vernon had a few over me. I had to stick in with Cooky. We both knew that it was going to be tougher for the guys coming in after us so we had to work through the hard times to put away any bad balls."
Stokes had one huge slice of fortune. Illness to Vernon Philander deprived South Africa of not just a dangerous bowler but a nicely balanced attack. And while Morne Morkel and Kagiso Rabada continued to bowl well, Chris Morris struggled with overpitching and was unable to maintain the pressure. Stokes took him for 26 in the 30 balls he faced off him and Toby Roland-Jones 15 from just six.
Had Stokes not absorbed periods without scoring, though, he might never have faced those spells. And he might never have had the opportunity to thrash Keshav Maharaj for 29 off 21 balls - including those three successive sixes to take him past three figures - or to cash-in against a tiring Rabada. He had forced those bowlers into extra overs and extra spells and persuaded Faf du Plessis to turn to his support bowlers.
Stokes had played Philander as well as anyone. Standing a stride or two down the pitch - perhaps to meddle with the length Philander was bowling, perhaps to ensure the ball came on to the bat with the pace he enjoys - he demonstrated his improving mental strength and defensive technique to deal with the ball nipping around sharply.
Mental strength may be key in these conditions. While other batsmen became flustered by the prodigious lateral movement - think of Heino Kuhn's intemperate swipe across the line when South Africa batted, or Maharaj's optimistic attempted force off the back foot - Stokes allowed himself a couple of rueful smiles when beaten by deliveries searing part his outside edge, then got his head down and played the next delivery on its merits.
This is how England should bat in Test cricket. There is still the room for the flamboyance that makes them so enjoyable - few batsmen can have brought up their centuries with successive sixes as Stokes did here - but it is most effective when tempered with some restraint and sophistication. Whereas, in recent times, they have sought to put pressure back on bowling teams by thrashing quick runs, here they did so by keeping them out in the field for over 100 overs - longer than they managed in both innings combined at Trent Bridge - and making South Africa work much harder for their wickets. And it was Stokes that led the way.
He may have started out as something of a wildcard in the England team, but he is maturing into a very fine player.