As soon as the last wicket fell, Kuldeep Yadav tossed the 57.4 over old red SG Test ball towards his senior colleague and the team's milestone man Ravichandran Ashwin, who promptly tossed it back to him.

After another round of catching, like an insistent older brother, Ashwin literally forced the ball into Kuldeep's palms. Ashwin had taken four in his 100th Test but Kuldeep did one better, a five-for that he had missed in the previous game against England.

But the 37-year-old's sweet gesture of depositing the ball in Kuldeep's hands may have subtly been a change of guard in terms of who the leader of the spin attack will be in the coming years.

Ashwin has had 21 wickets in this series with another innings to go and Kuldeep, who wasn't picked for the opening match, has 17 to his credit.

But in terms of impact, the man from Kanpur, after a roller-coaster ride in the past few years, has stood head and shoulders above his esteemed seniors.

The traditional 'Chinaman's leg-break', which turns in for a right-hander, sent back the opposition's best batter Zak Crawley and also brought back memories of Babar Azam's dismissal in the 2019 World Cup when he was at his absolute best in white ball cricket.

A beautifully tossed up delivery outside the off, luring Crawley into a lunge drive before sneaking in between the bat and pad, leaving the batter dazed. It was everything that makes up a left-arm wrist spinner's day-dream.

In a 2019 Test in Sydney, where he got a five-for, the then head coach Ravi Shastri had announced that he would be "India's lead spinner in overseas Tests", but that particular team management never walked the talk.

A subsequent loss of form and a career-threatening knee surgery pushed him further down the pecking order.

Those close to him recall how when he needed a comforting arm around his shoulder, Kuldeep had practically no one standing by him.

This is something that current skipper Rohit Sharma has managed to do with elan. If one checks Kuldeep's stats, he has felt more empowered across formats whenever Rohit has been the captain.

Kuldeep's childhood coach Kapil Pandey, a tough cookie from Azamgarh, a thoroughbred in Mumbai club cricket and someone who has navigated through the Kanpur maze wouldn't allow his ward to throw in the towel.

"He has three hat-tricks in white ball cricket but I completely understand that team combination is always paramount," Pandey, who runs his academy in Kanpur, told PTI during a recent interaction.

Kuldeep was back in his elements when he played against Bangladesh in December 2022, picking eight wickets and scoring a valuable 40, only to be replaced by a mediocre Jaydev Unadkat in the very next game.

But that Bangladesh series was the turning point for Kuldeep, feels Pandey.

"Before the tour of Bangladesh, we worked on his flight, line and length. The frame of mind for maximum bowlers now is that we don't need to use flight. It is just about containing the flow of runs and get wickets in the process like they do in T20," Pandey said.

How Kuldeep countered 'Bazball'

There are times when cricket as a game is over-analysed and solutions become complicated.

Pandey wanted his best student to follow his process of getting wickets in ODI games, where he has enjoyed commendable success.

"Aap batao Bazball hai kya? Old fashioned ODI cricket hi toh hai? (You tell me what is Bazball? It is just old fashioned ODI cricket," Pandey summed it up lucidly.

"In yesteryears' ODIs, a good score in 50 overs was 250 at five runs per over. Now just translate that to 90 overs and it is 450 runs in a day. That is exactly how England played the game. They took Test batting into ODI mode." "So, Kuldeep was simply told that way you bowl the way you bowl in ODIs. Bring that aspect of your bowling into Tests."

Tweaks in technique

Kuldeep, who looked miserable in Chennai during the 2021 home series against England, had a diagonal run-up with a slower arm-speed. That was the first thing that was changed.

"Post surgery, his run-up to the crease became straighter, arm speed increased. The moment arm speed increases, the balls spins at a higher speed." The next part, which was also the most important, was weight transfer while delivering the ball.

That is called pivot, where a spinner with his twist of waist, puts the entire weight of his body on the bowling shoulder.

"For a spinner, the pivot is weight transfer -- while he pivots, he needs to lean forward more, the classic example is Shane Warne. While pivoting, you would see how much his bowling shoulder used to lean forward, due to this transfer of weight. The ball would whiz at a faster clip while travelling through the air.

"Kuldeep also became better in using the footmark patches of his teammates bowling from other end." While training in Kanpur, Pandey always kept three left-handers and three right-handers ready for Kuldeep, so that if his rhythm was disrupted in match situations, he could deal with it.

"Earlier, he would pitch it a bit up and would always look at the batter. The Kuldeep that bowls now, concentrates on the good length spot instead of looking at the batter."

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