Wickets in the first over of your first T20I, off the first ball of your first ODI, and a rousing start to Test cricket as well - was the beginning too easy, in retrospect?
It definitely feels that way. The first one-to-two-year period was really easy for me. I was really enjoying it, but I didn't learn anything, because I didn't see any lows. It was during the year or two after that that I learnt the most about my career and myself.

What did you learn?
When I made my debut, my pace was at the most 130-132kph. When the batsmen realised I was swinging the ball, they started coming forward to me a lot more or tried to cut my swing. That's when I started trying to adapt.

You say you didn't learn much but the way you bowl indicates that you put in a lot of thought into understanding angles and working batsmen out. Was this a result of the two years when things didn't go that well, or have you always been like this?
It's naturally been in me, but in the first two years I was anyway getting wickets. There are many things - when it comes to bowling in a particular way, depending on who the batsman is - I have picked up later with experience.

You talk to seniors, you talk to coaches, but whatever I feel helps me - it could be watching any bowler in the nets, say [Mohammed] Shami, Ishant [Sharma] or Zaheer Khan, I watch what they do. Eighty per cent of whatever I have learnt is by watching other fast bowlers.

When I was a youngster, Praveen Kumar was in the same club as me, and because we are similar bowlers, I learnt a lot from him. We used to have conversations, but not a lot. What was very helpful was observing what he was bowling, the kind of fields he had, and what his thinking was.

"I wanted to increase my pace, but I had no clue how to do it. But after starting to do power training, I could see that I was getting stronger and my pace was increasing"

What is it with Meerut's bowlers and their natural affinity for swing?
Not just Meerut's bowlers. If you look at most of them from the north, they are largely swing bowlers. It's difficult to pinpoint a reason. It could be that balls are generally manufactured in north India, and when we bowl, the new ball is mostly in our hands, so we are probably more accustomed to the feel of it. And the cold conditions in the north support swing bowling, so that could be a factor as well.

If you are talking about being a thinking bowler, I benefited a lot by watching my seniors. When I started out, I wasn't a thinking bowler, but talking to seniors and coaches helped. They would always tell me that I ought to be clear about where I wanted to bowl before I ran in to bowl. As I started doing it regularly, it became second nature for me to first look at the field and make sure everyone was in the right position and then think about where I wanted to bowl.

Many young bowlers rely on their captain to set fields for them. Did you take responsibility for your strategy and fields early in your career?
Absolutely. When you are playing Under-17 or U-19, the captain is of the same age as the rest of us. His knowledge was also as limited as the other players, so there was greater responsibility on the bowlers to understand themselves and their bowling, read the pitch and set fields accordingly.

When I came to the international circuit, I also learned by watching MS Dhoni talk [to his bowlers] and set fields. When I watch a match, I always try to understand what the batsman is trying to do, so that I know what I should do to get him out.

When I discover something new, there is curiosity in me to learn it quickly. For instance, during the Australia series, I started bowling the knuckleball because I wasn't playing in the [first three] Tests. I wanted to pick up a new variation, so during lunch I would go to the nets and bowl the knuckleball from two steps. Sanjay Bangar and R Sridhar [the batting and fielding coaches, respectively] asked why I was practising it during the middle of a Test series. I said that Test matches required bowling on a length and reversing the ball, and as there wasn't much for me to do, I was trying to work on this. I couldn't use the knuckleball in the Test series [in the Dharamsala Test] because I was still learning it then, but it's proving quite handy in the IPL.

How long does it take for you to master a new variation like the knuckleball?
It took me around one and a half to two months to just get the control right for the knuckleball. Two months is generally a short time to master any delivery or gain 100% control over it. I won't say I have perfected the knuckleball. There is still room for improvement. I have used the ball quite a bit in the IPL, and have also taken a few wickets with it. I bowled it in a few matches at the start and had some success. When you take wickets with a new variation, your confidence increases.

The wide yorker doesn't take a lot of time to get right. You just need to change the angle. It hardly takes one week - not to perfect but to get the ball in that area.

During the Sri Lanka tour two years ago, you brought about a big change to your game by shifting to power training to boost your pace. Why?
I always wanted to bowl fast. Even before my international debut, I wanted to increase my pace, but I had no clue how to do it and I kept training like I used to in the past. When Mr Shankar Basu became India's trainer, he introduced power training. I used to work out in the gym before but I never felt that it had an impact on my pace. But after starting to do power training, I could see that I was getting stronger and my pace was increasing.

Which parts of the body do you focus on?
Power training is a full body workout. If you perform one exercise, it more or less improves every part of the body. When you do normal gym work, you work on particular areas. If you are exercising your leg, for instance, you work on your quadriceps or hamstring. But an exercise in power training includes everything from head to toe.

When did you first start noticing an improvement in your speed?
It was during the ODI series against South Africa at home [in late 2015] that we lost. That series was a turning point for me because my pace went from 130kph to 135-137kph. In that series I went for pace because I thought I was bowling quite fast, but it wasn't quick enough to trouble the batsmen. While the conditions were not very conductive for swing bowling, I also made a few mistakes in my search for pace.

After the series we had a break for almost a month and that was when I realised where I went wrong. Once I realised that, I got my swing back even as the pace increased.

When you try for extra pace, somewhere down the line the balance of your body gets affected a bit. Whenever I was looking to bowl quick, I was deviating from my natural angle and my body was falling over to the side. And my wrist position also wasn't as good as it usually was.

"When the captain looks at me, he should know I can bowl equally well with the new ball and at the death"

Who brought these technical chinks to your attention?
My coach told me when I went back to Meerut, but when I am bowling, I know what is happening with me. When I send down a delivery, I get an idea about what clicked and what didn't. The good thing is, before I go to someone else, I realise what the problem is. If I am learning a new variation or trying to bowl the inswinger or outswinger and it's not working, I figure out if the wrist or body position is the reason.

If the problems persist despite addressing these things, I speak to my colleagues or people who have known me for a long time. They point out that something [in my action] is looking a bit different. Occasionally, without you realising it, different things creep into [your bowling]. You look to identify those things and work on them.

Back then many people discouraged you in your attempts to increase pace because some bowlers in the past lost their ability to swing the ball in the pursuit of pace. Were you also apprehensive of that happening to you?
I wasn't apprehensive about it one bit. During the South Africa series, a lot of people discouraged me and criticised me. They were right. I wasn't doing what I was best at. When I went for pace, I didn't realise that [I had lost my swing]. The good thing is, by the time I realised this, my pace had already increased and I didn't have to work extra hard on it. And swing bowling is something I always did, so it didn't take too long for me to get it going.

Did you set a target pace you wanted to achieve?
I didn't set any targets because if you bowl normally, with 100% effort, it reaches the 135-140kph or 137-140kph bracket. That's my bracket, currently. I never look to bowl at 135 with swing and 140 with reverse.

So you are happy with whatever pace you can achieve with your natural body movement and action?
Absolutely. If you deviate from your body's natural movement and do something extra, then somewhere down the line, errors creep into your body alignment and wrist position. Then the line and length goes wrong and you develop problems with your swing.

You did well in the St Lucia and Kolkata Tests last year, but injuries notwithstanding, at times, you have been used only in seamer-friendly conditions. How do you reconcile with that?
I look at it positively, because when they played me in the West Indies, the coaches and captain knew the conditions there were suitable for swing bowling. Luckily, I also picked up wickets. I was then picked to play on a green wicket at the Eden Gardens, where again I got wickets. So you know that the team is supporting you. It's not like you are out of contention. Whenever the conditions are [conducive to you], you will play.

We have Shami, Umesh [Yadav] and Ishant, who are better than me when it comes to reverse [swing], when it comes to Indian conditions. But I know if the conditions suit swing bowling, I will be better. And this is something the management knows best, so they back everyone according to the conditions. That's the beauty of the team.

But you want to be an all-conditions bowler, don't you?
I wanted to increase my pace because I wanted to play Test matches in India. After increasing my pace, I played the Bangladesh Test. I took only one wicket but I was really happy with the way I bowled with the old ball. I played against Australia in Dharamsala, where the conditions were suitable [to swing bowling], but I was more happy with how I bowled with the old ball. I am slowly getting there. I am not saying I am as good as the other bowlers when it comes to reverse swing, but I am happy that I am better than what I was a few years back.

There are bowlers who bowl well but don't always have the wickets to show for their efforts. But you seem to have the knack of picking up wickets across formats. How do you manage that?
I think it's a mixture of everything - what you want to bowl, which batsman you are bowling to, and what fields you have for him. Sometimes you are looking to bowl a certain line and length to a particular batsman but the fielders aren't appropriately placed and you miss out on what could have been catching opportunities.

"If I am learning a new variation and it's not working, I figure out if the wrist or body position is the reason. If the problems persist, I speak to my colleagues or people who have known me for a long time"

In the last IPL, you spoke about bowling the yorker on leg stump to Dwayne Bravo to dismiss him in the second qualifier. You credited the wicket to having watched pre-match video analysis. Do you watch a lot of videos?
If we feel a team has a new batsman that we haven't seen before, then I go and watch the videos of the batsman. There is no point of repeatedly watching footage of someone like Rohit Sharma or Hardik Pandya. When you are playing alongside each other for a while [in the India team], you know what they would do. But, for example, Mumbai played Lendl Simmons, against whom I have played in the past. But I watch his video just in case he has changed something in his technique. I hadn't watched Rahul Tripathi before the IPL since I haven't played any domestic games against him. So I watched footage of him to see what he does. But more than videos, I try to watch live matches featuring these players. That helps me a lot more in understanding how someone plays.

Your death bowling, especially in the IPL, has improved considerably in the last couple of years.
When I started out [in ODIs], I used to take two-three wickets with the new ball, four if it was a good day. If you need to take four-five wickets on a regular basis, then you have to take wickets at the death. And to take wickets at the death, you have to bowl really well. It was an area I was really keen to improve because I wanted to be a complete bowler. I mean, no one is a complete bowler, but when the captain looks at me, he should know I can bowl equally well with the new ball and at the death.

The IPL really helped me improve that aspect. When Sunrisers Hyderabad picked me, I was already playing for India. They relied on me to bowl in those areas and when you keep bowling in the death, it really improves your skill.

What did you have to work on to become a better death bowler?
Increasing my pace helped a lot. I could bowl the yorker at good speeds. It doesn't mean that you will get the batsmen out, but if your yorkers are slower, it gives the batsmen time to get under the ball and hit you for boundaries. Then, like everyone else, I practised landing my yorkers on the right spot, and I also worked on my variations, like the slower ball and the knuckleball.

Death bowling is basically a mixture of variations. Sometimes you overdo it, which is why you go for runs. You have to assess the conditions, assess the batsmen and decide which variations work better. Sometimes if you miss a yorker by even a bit, you get hit. On a slower pitch, I go mostly with slower balls and cutters. I do bowl the yorker, but the majority of my deliveries would be slower ones. In a particular game, my slower grip might not be going well, or the ball will be rising well off the pitch, then I go with yorkers. It also depends on the batsman. If the wicket is not gripping but the batsman is not good against the slower ball, I still go with the slower one.

With batsmen constantly in and out of the crease and changing positions at the last moment, as a bowler, do your instincts take over completely?
Definitely. If you look at someone like AB de Villiers, who moves at the last moment, there are two things to consider. If I run in looking to bowl the yorker and he has moved away, it's down to me to bowl at the same place I had originally intended to or to follow him. Your first instinct tells you to follow the batsman. But earlier, when you followed the batsman, he would score runs off that delivery. So we began practising in the nets by placing three cones of different colours - one for the regular yorker, one for the wide yorker and one for the one on leg stump. The coach would stand at the bowler's end, and as we load up, he would shout out a particular colour and we would look to bowl there. I think that really helped, instincts-wise.

One batsman who has got the better of you at the death has been Dhoni. In Hyderabad you seemed to have worked out that he was severe on the fuller and yorker-length deliveries and started off with length balls. But then you went back to the wide yorker and eventually mixed it up. What was your plan?
The plan was to bowl length to him because he scores well off yorkers. But when I bowled length, I knew he was expecting it, and Dhoni is one such batsman who always tries to be ahead of the game. So I tried to mix up yorkers and length balls, because he's the kind of batsman that if you miss the yorkers even by a little bit, he is very good at hitting them for boundaries.

Last year, in the absence of Ashish Nehra you mentored Barinder Sran, a younger bowler. This year too, you have been seen talking a lot to youngsters like Mohammad Siraj. Does mentoring come naturally to you?
Being a senior player, I am just trying to help them. They are good bowlers, they are thinking bowlers and they have done well in the Ranji Trophy and domestic cricket. It's just about sharing the experience. I can't tell them "bowl this ball". But when I ask them what they are trying to do, I can help out. When it comes to the IPL, since I have played against most of the international players, I know what they will be looking to do, so I try to tell them what they can try against a certain batsman.

All Champions Trophy matches are going to be played in the south of England, where the weather isn't likely to be too cold. How effective will India's seam attack be in such conditions?
The pace attack will always remain effective in England because regardless of the conditions, the ball swings for at least eight to ten overs. Our bowlers all swing the ball and are quick as well. Our pace attack is quite balanced, especially for conditions in England. I won't say it is the best attack, but it compares well with just about any other attack.

How do India work around the disadvantage of not having played too many ODIs in the run-up to the tournament?
It's not a disadvantage. The positive thing is we are playing the IPL currently. The only thing we have to adapt to is the 30 more overs. We are playing two warm-up games before that, so that will be an advantage for us.

Arun Venugopal is a correspondent at ESPNcricinfo. @scarletrun