On the day when the selectors were due to announce India's T20 World Cup squad, ESPNcricinfo published a piece suggesting there would be intense debate over five spots, and that the other ten names were near-certainties.

When the squad was announced, one of the near-certainties was missing. The squad had no room for Yuzvendra Chahal, with Rahul Chahar leapfrogging India's highest T20I wicket-taker to the legspinner's slot.

"You want a spinner who can deliver with more speed," chairman of selectors Chetan Sharma said. "Recently we have seen Rahul Chahar bowling with speed. Our view was we need a spinner who can find the grip off the surface at a quicker speed and while we had a lot of discussion on Chahal, we eventually went with Rahul Chahar."

Chahal and Chahar are both fine bowlers, of course, and there was room for only one of them in the squad. And there were plenty of good reasons to pick Chahar, especially since he was, at that point, this IPL season's highest wicket-taker among spinners, with 11 wickets in seven games at an average of 18.36. Chahal had picked up four in seven at 47.50. Chahal's economy rate of 8.26 was more than a run per over worse than Chahar's 7.21.

At that point, the IPL was on pause, awaiting the start of its UAE leg.

The UAE leg is now well underway, and the Chahal-Chahar equation has flipped over completely. Since the IPL's restart, Chahal has been the most prolific spinner, taking seven wickets in four games at 11.14, while conceding only 5.57 runs per over. Chahar has taken two in four at 58.00, while going at 7.73.

The T20 World Cup, as you scarcely need reminding, will be played in the UAE.

The selectors couldn't have predicted what would happen in the UAE leg, of course, and anything can happen over four games, a tiny sample size in T20. Chahar may yet go on and have an outstanding World Cup. He may well go on and enjoy a storming finish to his IPL season before that.

This isn't an argument for Chahal or against Chahar. India simply have plenty of quality spinners to choose from, and a limited number of slots to fit them into. Someone had to miss out, and it happened to be Chahal. It happens.

But since it's happened, Chahal has shown once again what a canny operator he is in the shortest format, and his display against the Rajasthan Royals contained all the classic Chahal virtues.

There is merit in the India selectors' desire for quick spinners who hit the shorter side of a good length, test both edges of the bat, and attack the stumps relentlessly. Spinners like Chahar, or Varun Chakravarthy, or Rashid Khan, or Sunil Narine. When they're on target, they're extremely difficult to hit, especially down the ground.

Chahal is different, slower through the air and more willing to dangle a carrot at the batter. He generally bowls two lines to the right-hander: flatter on middle-and-leg to deny them room to free their arms, and wider with more loop to dare them to take him and the boundary fielders on.

It's the age of quick wristspin, but Chahal had shown once again that a little bit slower can be just as effective

When he bowls the straighter line, his legbreaks tend to come out of the front of his hand, with more sidespin, and skid on off the surface, while the wider-line legbreaks come out in the classic manner, delivered with as much overspin as sidespin and with the seam pointed to slip.

There isn't a lot of margin for error at his pace, and you saw this with the last ball of his first over against the Royals. It was the wider legbreak, but he overpitched slightly, and Sanju Samson lifted it smoothly over extra-cover for six.

At that point, the Royals were 100 for 1 in 11 overs. Evin Lewis was batting on 58, and with Samson at the crease and Liam Livingstone to follow, they seemed poised to get at least 180.

They ended up with just 149, and multiple Royal Challengers bowlers contributed to this, not least George Garton bouncing Lewis out at the start of the 12th over, and Shahbaz Ahmed getting two batters caught in the deep in the 14th.

Chahal ensured there was no coming back for the Royals, heightening the new batters' uncertainty with his changes of pace, and asking them to step out of their comfort zones to try and get after him.

In the 13th over, he saw Mahipal Lomror step out of his crease, and dangled a wrong'un across the left-hander and away from his hitting arc. He swung down the wrong line, and KS Bharat completed a neat stumping, adjusting smartly for extra bounce as he gathered the ball.

It was the 14th stumping off Chahal's bowling in the IPL. Only Amit Mishra (28), Harbhajan Singh (18) and Piyush Chawla (14) had induced more stumpings previously, and all three have played upwards of 150 games. Chahal has only played 110 so far.

"He's a world-class bowler, like we all know, and he varies his pace exceptionally well," Bharat said in his post-match press conference. "You have to be in the game every ball, you just can't fade off even for a single moment. I was just trying to keep myself in the game, and to read him from his hand, and we all know the lines and lengths he bowls, the keeper is always in the game each and every ball, so you've got to be in the game, and you just enjoy the sport."

Virat Kohli had waited until the 11th over to introduce Chahal because the Royals had had two left-handers at the crease for the bulk of the first 10 overs. This meant Chahal still had an over left when the death overs (17-20) began. Kohli kept his legspinner going, with Livingstone at the crease as the Royals' last danger man.

Until then, Chahal had bowled three balls to Livingstone across two overs, firing everything at leg stump and giving him nothing to go after. Now, when Livingstone came back on strike, he sent down that familiar tempter wide outside off stump. Go on, fetch me if you can.

Livingstone tried to do just that, but as so many batters have done before him - not least Chahal's now team-mate Glenn Maxwell - he discovered the treachery of that loopy, wide legbreak. It looks hittable, but the slowness and overspin combine to almost always ensure that it lands a foot or so short of the batter's hitting arc.

The batter is forced to reach for the ball, and invariably loses his shape as he does so. Livingstone held his shape better than most, but he couldn't find the power to clear the man at long-on.

Chahal made it all sound matter-of-fact when he described the dismissals at the post-match presentation.

"For Lomror, I knew he was coming out [of his crease], and I had watched his videos so I knew he was very good on the leg side, and then I planned, okay, if he's coming out, I'll bowl wider, let him hit over cover," Chahal said. "And with Livingstone, because the shorter boundary is [on the leg side], I wanted him to hit over cover, because the bigger boundary is [on] that side, and I don't want to bowl faster, I just want to bowl a little bit slower to him."

It's the age of quick wristspin, but Chahal had shown once again that a little bit slower can be just as effective.

Karthik Krishnaswamy is a senior sub-editor at ESPNcricinfo