"Sir, basically the ball goes inside, outside and goes straight. So, you can keep it that way but there are minute changes that you can do with that also."

From a mystery spinner, you can understand the secrecy. In fact, it's kind of a boss move.

Varun, by his own reckoning, did not consider cricket a serious professional endeavour until he was 26. "Before that, my dreams were all being an architect and making movies. So, I've had different career paths."

And yet here the guy is, at 33, taking 5 for 42 in the second ODI he has ever played, making a very serious case for his inclusion in the semi-final of the Champions Trophy, which is also likely to be played on a used surface that is likely to favour him. Varun is an IPL graduate, having played only a single first-class match.

He explained how he figured out how to bowl in 50-over cricket, having initially come from the T20 world.

"In T20, my sequencing of balls - as in how I construct an over - is totally different compared to the 50-over format," Varun said. "And that I was able to figure out when I played the last two years in Vijay Hazare Trophy [India's main domestic one-day tournament]. And it really helped me to understand when I can bowl my incoming delivery or outgoing delivery or the straighter one or the top spin - whatever it is. But that gave me a sense of awareness of when to bowl what. It is completely different from what I do in the T20."

In this match against New Zealand, Varun said he didn't feel a ton of pressure, because of the presence of Kuldeep Yadav, Ravindra Jadeja and Axar Patel.

But there is also the pressure not to reveal what he has in store for teams about to face him in the rest of the tournament. Or even for teams that will face him in the IPL to follow. Varun is not giving out trade secrets to any of these fellows, even if they happen to be in his own team.

"But he has got something different which is why he is here with us. He has been impressive in the last eight to nine months. That is why we wanted to bring him here and see what he has and what he can do for India on the big stage."

What he has done for India on the big stage is suggest he should have more ODI appearances, particularly on used pitches. The surface for the semi-final against Australia will likely be on the same pitch they had played Pakistan on.

Varun, who didn't play in India's first two Champions Trophy matches, has now made himself very difficult to drop.