Since Kuldeep Yadav's debut, in June 2017, there have been 3658 balls of left-arm wristspin bowled in ODI cricket. Kuldeep has bowled 2298 - nearly 63% - of those. He has played 44 ODIs, five other left-arm wristspinners have 31 caps between them. None of them is in any first XI in this World Cup.
Yuzvendra Chahal is a right-arm wristspinner unlike others. Most teams have come around to using wristspin in limited-overs cricket, but other wristspinners bowl much faster than Chahal, who goes slower and slower whenever put under pressure.
Good as the duo are, the biggest challenge for teams is they get no practice against that kind of bowling. This is one thing batsmen keep telling their analysts, especially with Kuldeep. It is incredibly difficult to pick him when you are playing his kind of bowling straight in a match situation. No bowling machine can simulate what he does. Left-arm wristspinners as net bowlers are difficult to find as it is; the ones who turn up are not that great.
Aside from Japsrit Bumrah - who is just as hard to replicate - the biggest threat for batsmen remains the left-arm wristspin, and to a lesser extent, Chahal's slow legspin. England have tried the bowling machine Merlyn, but Australia have chosen a more human route. Travelling with them as official part of their support staff are two legspinners from India.
One of them, the right-arm one, Pardeep Sahu, has played first-class cricket for Haryana and IPL for Kings XI Punjab and Rajasthan Royals. He struggled to get past Amit Mishra and Chahal in the Haryana team that often, and began to look elsewhere. The other, KK Jiyas, is a left-arm wristspinner from Kerala. He is a Glenn Maxwell-lookalike - his nickname back home is Kerala Maxwell - and has had observers do a double take on whether Maxwell has started bowled left-arm wristspin. He never got to play for Kerala.
The common link between them is that they both trialled at Delhi Daredevils when S Sriram, the former India batsman and now Australia's spin consultant, was with them. Jiyas was even bought by Daredevils at the 2015 auction, but never got to play in the first XI.
Jiyas was first used in the nets by Australia during the ODI tour of India in 2017-18. Sahu was added to the group on Australia's UAE tour in 2018-19. They are a bit of a recruitment coup for Australia, in that they are not just any club bowlers, but pretty decent legspinners that IPL sides considered recruiting.
Sriram is arguably a bigger recruitment coup. He was one of the best batsmen of spin in his era. Australia got him into their set-up on an operational basis back in 2015, specifically to help their batsmen with spin. His work showed results on the 2016-17 tour of India when they came within one good innings of winning the Test series. Sriram was told of Jiyas by TA Sekar, who has also worked at Daredevils.
"It's easy to come up with ideas, anyone can come up with all these ideas but to actually get the Indian spinners to come and be with us, I love that," coach Justin Langer said in the UAE last year. "I love that we had a plan and we executed, hopefully, we get some benefit out of it."
Clearly the batsmen were impressed enough with them to bring them to the World Cup. The two are staying with with the Australia team, they wear their training kit, and at the nets in Bristol they have been bowling more than even the bowlers in the squad.
On Sunday, Sahu beat Steven Smith two times out of the first three balls he bowled. One of them had Smith walk past the legbreak. They have been giving the Australia batsmen quality practice to face both kinds of wristspin, and if they do manage to get the better of India's threat, there will have been an Indian hand in it.