Good areas. You hear that phrase all the time, and you probably groan when you do, because a: you hear it all the time, and b: what does it even mean?
It may be a cliché, but Test cricket is all about good areas. If you get down to the core of it, a good area for any bowler is one that keeps the three classic modes of dismissal in play: bowled, lbw, and the outside edge to the keeper or the slips cordon.
Figuring out where this area is, of course, is easier said than done. A good area, for the same bowler, could occupy an entirely different patch of turf on a first-day pitch in Delhi compared to a first-day pitch in Nagpur.
This, it seemed, was the challenge that faced India's spinners on Friday. Low bounce had been a defining feature of the Nagpur Test, and it had played a large part in shaping both teams' strategies. Delhi was different.
R Ashwin discovered this with his sixth ball of the Test match, in the seventh over of Australia's innings. It drew David Warner on to the front foot to defend, and leaped from the surface to strike the outside shoulder of his bat and roll away past slip.
Through his next few overs, Ashwin continued to trouble Warner and Usman Khawaja with his turn and bounce, going past the outside edge multiple times. But there was also a sense during this passage of play that the bounce could be an ally to an opportunistic batter.
Khawaja was certainly in an opportunistic mood. He stepped out in Ashwin's third over and launched him for a straight six, and reverse-swept and swept him for fours in his sixth and seventh overs.
If you get close enough to the pitch of the ball, you can play lofted drives far more confidently when there's a bit of bounce: it's likelier that the ball will hit your bat's sweet spot rather than low down near its toe. And though bounce amplifies the threat of a top-edge while you sweep or reverse-sweep, it reduces the threat of bowled or lbw if you miss the ball.
Runs were coming at the other end too, even if the batters weren't always in control, as Australia met aggressive bowling with positive intent. Warner copped a pair of blows from Mohammed Siraj's bouncer before nicking off to Mohammed Shami, but hit three fours in between. In that time, the quicks also conceded two fours to Khawaja, one off either edge of his bat.
Marnus Labuschagne, Australia's No. 3, also exuded positive energy, driving Shami to the cover point boundary, dancing out to whip Ashwin over midwicket, and sweeping Ravindra Jadeja hard and flat for another four. Jadeja, against whom Australia struggled both to survive and score runs in Nagpur, went for two fours in his first over.
It was a fascinating contest, India bowling well and Australia scoring quickly regardless. When Ashwin began his ninth over with 15 minutes to go for lunch, Australia were 88 for 1, hurtling along at exactly four an over.
Australia have an unusual number of left-hand batters in their top order - five of their top seven in both Tests of this tour. Ashwin's match-up against them has been a constant talking point, to the extent that India's players - KL Rahul two days before the Nagpur Test and Rohit Sharma at its conclusion - have taken care to interject, when that conversation has come up at press conferences, that Ashwin is just as good against the right-handers.
On Friday morning, Ashwin let his bowling speak for itself.
Bowling from around the wicket, Ashwin drew Labuschagne forward with the fourth ball of his over. This was a proper, old-fashioned offbreak, delivered with as much overspin as sidespin, and there was both drift across Labuschagne and a bit of dip.
The drift drew Labuschagne's front pad across to the off side, and the dip caused the ball to land ever so slightly shorter than he may have expected. It landed, in fact, on just about the perfect spot for this Delhi pitch: full enough to ensure it wouldn't bounce over the stumps, but not so full that Labuschagne could get close to the pitch of the ball to smother it.
Labuschagne's front leg ended up solidly in the line of the ball as it spun back into him, and his bat ended up having to slice across his pad to access the ball. He missed, and Ashwin went up in righteous appeal - DRS went on to validate his instincts, showing that there was no inside edge, and that ball struck pad in line with off stump.
It was a gorgeous bit of bowling, and a warning to every batter to follow. India fans know this moment well, this moment that has come so many times in Ashwin's career, seven or eight overs into his first spells, the moment when all of Ashwin's micro-adjustments - little tweaks to the speed and angle of his run-up, his load-up position, and the degree of his rock-back prior to delivery - put his action in just the right rhythm to bowl at just the right pace, trajectory and length for the surface.
That moment had arrived, pregnant with possibility.
Over his career, Ashwin has made a habit of repeating his party tricks - whether it's getting Kumar Sangakkara caught in the slips in the last three innings of his Test career, or bowling the dream offspinner's ball - pitch leg, hit off - to Alastair Cook twice in the same Test match, or bowling Ollie Pope twice in the same Test match, in near-identical manner, once from round the wicket and once from over.
Now Ashwin played a different sort of party trick, pitching two balls on more or less the same spot, once to Labuschagne and once to Steven Smith two balls later, and getting them to behave in entirely different ways.
How much of this was intentional is debatable. Ashwin's release differed only by degree, the seam of the ball perhaps pointing to leg slip against Labuschagne and leg gully to Smith, but both times there was overspin as well as sidespin, and both times the seam wobbled just before the ball landed.
It would be far-fetched to think the wobble was intentional, but it certainly made the two balls land differently - one on the seam, probably, and the other on some part of the leather, probably. The Labuschagne ball turned, and the Smith ball kept going with the angle across him.
Natural variation, but Ashwin had maximised its threat by hitting that perfect spot on the pitch.
Six years ago in Pune, Smith played one of the great Test innings by an overseas batter in India, a match-winning third-innings century that was a triumph of method over natural variation. His strategy, then, had been to try and protect his stumps every ball. This meant playing for Jadeja's straighter one, and for Ashwin's offbreak - if the ball went the other way he would allow himself to be beaten on the outside edge, refusing to let his hands get drawn towards the ball.
In Nagpur, Smith had twice been beaten on the inside edge by Jadeja's straighter one - bowled in the first innings, and reprieved by a no-ball off a similar delivery in the second.
Now in Delhi, Ashwin drew Smith's hands away from his body, and drew a thin edge to the keeper.
You could construct, out of these three dismissals, a narrative of Smith's weakening game against spin. Or you could simply see them as an illustration of how difficult it can be for any batter, even the best batter in the world, to keep surviving against Jadeja and Ashwin when they get their pace, trajectory and length just right.
In both Tests, moreover, Smith was dismissed by non-turning balls soon after seeing other batters dismissed by sharp turn. Errors are inevitable when deadly accuracy meets natural variation, and you need luck to survive them. It's just the way of cricket. Luck was on Smith's side in Pune, and it's gone against him in this series.
On Friday, Ashwin earned that little bit of luck by hitting the perfect spot, twice in the same over. In a career full of magic deliveries, this may well have been his most magical over.