Genius is hard to describe. AB de Villiers scored an unbeaten 73 off 33 balls on Monday night against the Kolkata Knight Riders, on a pitch where everyone else made 218 off 207, and while that's obviously extraordinary, it didn't look extraordinary.

Or let's put it this way. It didn't look differently extraordinary.

It looked like any other extraordinary T20 innings de Villiers has played. He didn't stand differently at the crease, or grip his bat differently, or play any shots you haven't seen before. There were no new tactics devised on the spur of the moment to combat a slow and grippy pitch where every other batsman struggled for fluency. It was just AB de Villiers batting like AB de Villiers.

It was the kind of innings that makes you reach for supernatural explanations. Virat Kohli faced 28 balls in the same innings and hit just one boundary, off his outside edge. He watched all of de Villiers' innings from the other end, and at the presentation ceremony called him "superhuman". He spoke of the "zing" in de Villiers' eyes. de Villiers himself said he'd felt an "energy" when he'd got on the bus to the stadium, and felt "a bit of light out of my eye".

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There were certainly moments during de Villiers' innings when a ghostly light seemed to shine from his eyes. Something not quite of this world seemed to take place, for instance, when he drove the third ball of his innings straight back down the pitch. The ball hit the stumps at the other end, deflected by some 45 degrees, beat mid-off's dive to his left, and kept running away from that fielder even as he sprang up and gave chase, seeming to accelerate as it approached the boundary as if the laws of physics had been briefly suspended.

As remarkable as the innings was, though, we know it was bat and ball and flesh and blood, and it was all explicable in some way. Kohli got to the essence of it.

"I just have to say that a lot of people can do what you've seen in the other games, but on a pitch like that, to bat like that, I think it's only AB who can do that, just because of the way he sets up and he's so still when he's seeing the ball clearly and he's so dangerous, because he can wait for the slower balls and deposit them out of the stadium, so it was a special knock," Kohli said.

Still.

That word gets to the heart of what makes de Villiers so good. This was a pitch so slow that de Villiers didn't once dip into his considerable repertoire behind the wicket, and he consequently did not move around the crease as extravagantly as he often does. But even when he moves all over the place, he's perfectly still at the moment when the ball leaves the bowler's hand.

The quickest feet in the business, and the stillest head.

Sometimes, the moments that best illustrate what makes someone like de Villiers tick are those rare moments when something goes wrong, when the finely tuned inner machinery of his game misses a beat.

Take the second ball of the 16th over, a slower offcutter from Kamlesh Nagarkoti, clocking 112.1kph. It was the kind of delivery that had frequently wrenched batsmen out of shape throughout the Royal Challengers Bangalore innings, up to that point, and it wrenched de Villiers - batting on 10 off 10 - out of shape too. He swung too early at it, missed, and ended up getting hit on the thigh pad.

It was an illustration of everything that usually never happens when de Villiers bats - a loose, imprecise swing with bat reaching out too far in front of his body, causing a loss of balance that tips his head to the off side at a most un-de-Villiers-like angle.

When everything is working well, de Villiers' bat-swing is like a golf swing. He mentions this in this video, where he explains what he calls his "box theory".

"I always talk about a little box that's around me," he says. "I don't want any part of my bat, feet, head, nothing, to leave this box. Everything must happen in this box, because that's where I have all my power, right here, in this box, everything to be played right here.

"In golf, they talk about a compact golf swing. You've got to feel like you're almost swinging in a box, and it's the same with my batting."

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de Villiers had reached out of that box against that Nagarkoti slower ball. But that's what good slower balls can force batsmen to do on sluggish pitches, offering them no pace and asking them to manufacture all the power themselves.

Where other batsmen might look for other ways to compensate for that lack of pace - by batting out of their crease, perhaps, to meet the ball earlier - de Villiers simply went back into his box, stretching, by a fraction of a second, that moment of stillness that defines him.

It sounds simple when you read it, but it surely isn't. You're working against your muscle memory, which has been honed over tens of thousands of balls on mostly quicker pitches, and while every innings involves a recalibration of muscle memory - it's what "getting your eye in" essentially means - it takes a freakish level of ability to do it in the space of 11 balls on a pitch like this one in Sharjah.

Watch the next two balls that follow the ball that beats de Villiers. They're slower offcutters too, delivered at similar speeds (116.6kph and 114.8kph), but de Villiers holds his shape for longer against them. It's often said that the best batsmen have more time to play their shots; against these two deliveries, de Villiers is poised and waiting for what seems an eternity.

His back foot has stepped across to off stump in his trigger movement, and his wrists are cocked, holding his bat up just above the flap of his right pad. His head, having dipped slightly at release, is still, eyes perfectly level. Everything, in that moment that stretches and stretches, is still, as he waits for the ball to enter his box.

In his box, out of the park. The first one's just a touch short, and he opens up and swats it over midwicket. It goes over the stadium roof and into the speeding traffic. The next one's full, angling into leg stump, and he clears his front leg and unleashes that golf swing, his bat finishing over his left shoulder as the ball clears another roof, beyond long-on this time. One more dent in one more car.

It looks absurdly simple. You tell yourself, hey, those slower balls are getting predictable now. Perhaps the lengths are wrong. But de Villiers keeps doing it, over and over, while at the other end, and at other times in this game, other batsmen, fine batsmen, struggle. Look closer, then. Maybe there is a light shining out of his eye.