In the last two years, Jasprit Bumrah has been the find of Indian cricket. His initial success might have had something to do with his unorthodox action, but as batsmen around the world got used to playing him, the accuracy with which he could execute bowling plans came to the fore. He's India's best bowler in white-ball cricket, and the tour to South Africa showed that he could be an asset in red-ball cricket as well.

There are many things going in Bumrah's favour, but let's start with the aspect that brought initial fame and success - his action.

In a bowling action the arms work on the same principle as the two pedals on a cycle. One goes up, the other stays down, and the moment the first one starts its downward journey, the second one starts moving upwards. That's how the two arms function in the bowling action too - when the non-bowling arm goes up while loading, the bowling arm stays low, and when the non-bowling arm starts moving downwards, the bowling arm propels upwards. In fact, it's believed the higher the non-bowling arm, the better the control and pace generated by the bowling arm.

Bumrah in international cricket Format M W Ave Econ SR Test 3 14 25.21 3.14 48 ODIs 37 64 22.5 4.64 29 T20Is 34 41 20.43 6.85 17.8

Bumrah is an aberration in this aspect since his non-bowling arm never goes higher than shoulder height, and unlike other bowlers, his non-bowling arm isn't bent either. There's a specific mark in his action when both arms are almost parallel to each other.

Batsmen are tuned to follow cues in a bowler's action. The downward journey of the bowler's non-bowling arm is a signal to the batsman that the bowling arm is getting into play and so it's time to brace for action. It's not a surprise that batsmen were a fraction late, and therefore less synchronised, when they faced Bumrah for the first time.

For the longest time Indian cricket has been averse to unorthodox bowling actions. Perhaps it was the colonial influence steering Indian cricket to discourage anything that wasn't mentioned in the coaching manual. It's not that bowlers with unorthodox actions never played professional cricket in India, but they were seldom encouraged. The coaches at the junior levels were hardwired to nip this problem (yes, it's considered a problem) in the bud. The rise of Bumrah might not have been possible in the pre-IPL era because the national selectors' conditioning might have coloured their judgement.

Bumrah in the 2018 IPL M O R W Ave Econ SR Overall 14 54 372 17 21.88 6.88 19 First 7 games 7 28 202 8 25.25 7.21 21 Last 7 games 7 26 170 9 18.88 6.53 17.3

How he added to his unusual action

In addition to his action, Bumrah also had the ability to bring the ball back in very sharply to right-hand batsmen and to get the ball to hit the bat hard. The fact that he bowled from the corner of the box, with the wrist pointing towards fine leg at the point of release, just accentuated the angle.

You will have heard commentators use the term "heavy ball", which refers to a delivery that tends to come in a shade quicker and hit a little higher on the bat than expected. Bumrah does both.

Will we see Jasprit Bumrah feature in the Tests in England after his success in South Africa? AFP/Getty Images

But in the first 12 months of his international career, he also started getting closer to the stumps at the point of release and straightened his wrist, with the seam upright and not slanting towards fine leg. While he has always been capable of bowling sharp inswingers, he has learnt the art of making the ball either hold its line or move away from the right-hand batsmen by just straightening his wrist a little.

And he must be the only bowler (with the exception of Dwayne Bravo) who is extremely successful in white-ball cricket without bowling the knuckleball or the legbreak variation of the slower one. The offcutter/break is the easiest variation of the slower delivery, but it's also the easiest to pick and to hit, so most bowlers have developed the knuckleball or the back-of-the-hand slower one or the legcutter variation.

While Bumrah's quick-arm action (read: unorthodox) makes it tough for the batsmen to read his subtle variations, the success of his slower delivery lies in the length he bowls and the bounce he gets. Unlike the slower ones from other bowlers, his slower ones tend to have a slight parabola-like trajectory that hold the surface and bounce a little more.

Bumrah in the death overs in the 2018 IPL Runs Balls Econ W Ave First 7 games 98 66 8.90 7 14.00 Last 7 games 59 54 6.55 6 9.83

How Test bowling affects white-ball bowling and vice versa

In the first game of the IPL this year, Chennai Super Kings needed 27 in two overs with Bravo on strike. When Bumrah came on to bowl the 19th over, I was convinced the match was sealed and delivered in favour of Mumbai, the home team. But it wasn't the case, and while that had a bit to do with Bravo's excellence, it also had a lot to do with Bumrah's yorkers not landing in the desired spot. He's one of the best death-over bowlers in the world because of his accuracy with yorkers, but he didn't get them right that night -- or even against Rajasthan Royals two weeks later.

Many argued that Bumrah was no longer the same bowler and that batsmen had figured him out. The moment you fail to deliver perfect yorkers, the slower ones also lose their potency. The success of both is interlinked. So what went wrong?

Since Bumrah rediscovered his mojo by the time the business end of the tournament came around, it's only fair to assume that training for red-ball cricket might have played a part in his yorkers not finding their spot earlier on. Bowling is all about muscle memory - the more you practise a particular skill, the better you become at executing it. When you're playing only limited-overs cricket, you practise only those skills and eventually get close to mastering them. But preparing for and playing Test cricket demands bowling a different line and length for longer periods of time. The number of balls you need to bowl in order to be Test-ready, and then the number of balls you actually bowl in a Test series, will automatically train your muscles to behave a certain way. And it will, once again, take an equal number of balls to realign the muscle memory to meet the demands of T20 cricket.

It will be interesting to follow Bumrah's career for the next 12 months. I'm certain he will be in the playing XI for all the Tests played with the Kookaburra ball. He's one of the few Indian fast bowlers who hits the deck hard and is effective even after the ball gets old. Since India are playing a five-Test series in England (with the Dukes ball), he might be needed to turn up for a few Test matches there too. It will be prudent to manage his workload and give him enough downtime to move from one format to the other, because the World Cup isn't far away and his white-ball skills hold the key to India's success in the marquee event in 2019.