No IPL in India goes by without dew becoming a talking point. It has an impact on the toss and overall game plans. The 2021 tournament has been no different, with MS Dhoni, the Chennai Super Kings captain, saying the early start times (7.30pm as opposed to 8pm) give an unfair advantage to the team batting first because the dew is yet to set in. KL Rahul, the Punjab Kings captain, suggested teams bowling second be allowed to change a wet ball.

What exactly is the problem that dew poses, particularly to fast bowlers in the death overs? We asked former international fast bowlers Dale Steyn and Ajit Agarkar to break down the challenges.

What happens to the ball when it is wet?

Ajit Agarkar, former India fast bowler: It's leather, so the water keeps seeping in, the seam becomes greasy, and it is very difficult to hold the ball on the seam.

Personally, because my foot landed at an angle and then there was a pivot, I used to struggle a lot if the bottom of the shoe was a little wet or greasy, or if there was a lot of mud on it. When the foot landed, it didn't stick in the [damp] pitch for the pivot to happen; and when the foot slipped, I had no control of what happened at the other end.

When the ball is slipping through your fingers, you don't really have control over the length. You set the field for a particular ball but the execution doesn't happen like you want it to.

Plus, it skids off the pitch, which becomes a little bit easier for the batsman. To consistently bowl the balls you want becomes a lot harder.

Dale Steyn, former South Africa fast bowler: I back everything he said. Your run-up becomes difficult when you land. You feel like you are a little bit unstable because you can slip. The ball becomes extremely greasy in your fingers. The seam and the leather just become extremely slippery.

And once the ball hits the deck, it also loses that bounce, because it is now a little wet. So if you were to going to bowl a back-of-a-length ball, it often doesn't get as much bounce, which means that if you like to hit the stickers of the bat, now you are hitting more of the centre of the bat, where you don't exactly want to hit.

The ball actually completely loses its swing. So if you are thinking at the back end of an innings to target a little bit of reverse swing or get the ball to dip, because it's dry on one side and a little wet on the other, that goes completely out the window too.

A slippery, greasy, wet ball is probably one of the most difficult things to control when it comes to bowling.

Can you practise by getting the ball wet during training?

Steyn: You can. It is less practice with the ball and more mental practice - training your brain that this is the situation. You can't exactly create the same amount of dew in practice as you would have in a game. No two [wet] balls will be the same. You can't be certain the ball is going to be this wet as opposed to a dry ball, where you know, okay, I can run in and if I let it go like this, it's gonna land exactly there. It is really just training your brain to understand that this is going to be extremely

"Jasprit Bumrah he looks like he just nails his yorker regardless. Lasith Malinga was another one that just seemed to, regardless of the dew, nail his lengths"
Dale Steyn

When you are doing it in practice, and you get maybe seven out of ten, you do feel a little bit better as opposed to going out in the game and it being completely foreign to you. You are just thinking to yourself, "That's it, this game is over", when, effectively, you could get the ball in the right place having known you have done it in training.

So you can't exactly simulate the situation while preparing?

Agarkar: Obviously not. Plus, the ground is not wet either [during training]. I mean, try bowling with a wet bar of soap. It can be practically impossible when there's a lot of dew. It makes life easier for the batsman, but as a bowler it just becomes so much harder to land the ball on a spot. Then it becomes difficult to control the runs as well.

Does the dew hurt more when you are bowling second?

Agarkar: It gets progressively worse as the game goes on. That's why one-day [day-night] games now start a bit earlier in India - at 1.30pm as opposed to 2.30pm. The team fielding second are at more of a disadvantage because it just keeps getting worse. It does not matter how much chemical is sprayed or how much the rope [to mop up the dew] goes around or [whether] the Super Soppers are used.

How does dew tend to mess up bowling plans at the death?

Steyn: Sometimes you are thinking of a particular way you want to bowl. You go "Okay, cool, tonight you know the plan is that to this batsman we are going to bowl yorkers." And then you come across the dew factor. I've seen many a bowler running in and bowl two waist-high full tosses, almost shoulder high. And that's it. You are out of the attack. It can really go pear-shaped.

That's when you have to start to think on your feet a little and drag your length back.

Commentators or people watching the game might start to go: "Why did that guy bowl a back-of-a-length slower ball as opposed to running in and bowling a yorker when we know that, as an example, [Kieron] Pollard's not good at [facing] a yorker?"

That really is because you are scared that the outcome is not going to be what you want it to be. You have bowled one yorker and it's a full toss. You have been given the warning. Now your captain comes to you and says, "Another one like that, my friend, and you are out of the attack." So you start to change your thinking.

So what is the best length to bowl in such situations?

Agarkar: It depends on the day. There might be days where it is wet but you are still getting the ball full enough or landing it well. I found it a little bit easier to bowl length. My [bowling] arm was anyway a little bit lower, so the ball did skid through and if I did bowl that in-between length, I had a chance of getting away with it if there was no real room or it wasn't too short. Maybe the batsman can't time it properly [against the skidding ball] if you are straight enough.

The yorker is the toughest ball to get right when the ball is wet, because from landing on the crease to keeping your action depends on trying to bowl full and quickly. Cross-seamers are something that a lot of bowlers try because it becomes difficult to grip the seam [upright], but the control or execution of every ball then becomes a challenge.

Steyn: I preferred to bowl a hard back-of-a-length. Bowling a yorker is hard at the best of times with a normal ball. And now you are trying to do that with this wet bar of soap. It becomes impossible.

In T20 cricket, at least, you are using one ball. When you are playing one-day cricket, you can be bowling from the one end and the ball might not be as wet, and you are absolutely nailing your yorkers. But then your captain switches you to the other side. You run in, bowl a full toss and you just know you've got to completely change your game plan. I have to go cross-seam and bowl hard lengths. You really have to play it on how you are feeling out in the middle, explain it to your captain, get the right field setting, and you just have to back it and hopefully it comes off.

Are there some bowlers, in particular, who have done well in these conditions?

Steyn: I have never really played with somebody like Jasprit Bumrah, but he looks like he just nails his yorker regardless. Lasith Malinga was another one that just seemed to, regardless of the dew, nail his lengths. But I guess that was his go-to ball. He just felt confident he can do it. And maybe the guys who run in slightly slower. When they land on the crease, they are more in control of themselves. They are probably going to bowl at the same speed, but everything is a little bit more in control.

And like Ajit said, when running in as a fast bowler and trying to bowl as quickly as you can, a little bit of a slip here, a little bit of a movement here - this game is by inches. You miss your yorker, it's a waist-high full toss, and the ball goes out of the ground.

So probably for Bumrah and Malinga, the dew never seems to bother them, but I can guarantee you, for the rest of the world, it's always in the back of your mind.

Some IPL captains have suggested the ball be replaced during the second innings to compensate for the dew. What do you think?

Steyn: Yeah, it can be. But then, you know, teams are also going to be holding out against it because the team that batted first may not have had the ball swapped over as many times.

What about a pre-decided change for both innings?

Steyn: I guess so. Also, for the safety of the sport. You are going to be running in and looking to bowl yorkers. There's a chance that the ball can slip out of your hand. When I played a game for the Royal Challengers last year, I actually asked the umpire: "Please, can we change this ball? This is a crucial time of the game and I feel like I'm going to bowl a waist-high full toss." He opted not to. I had to bowl the back-of-a-length ball.

It was the last batter. He got under it and got caught on the long-on boundary. Had they changed the ball and had it been a newer ball, it probably would have gone for six. So I was both lucky and unlucky at the time. Maybe if you are looking to come into the back end to bowl and there is extreme dew, changing the ball is the best way. But you'd be almost doing it once every two or three balls.

Agarkar: That seems to be the best solution. How you get it done is a challenge. Certainly it is a completely different ball game when it is a drier ball in your hand.

Nagraj Gollapudi is news editor and Raunak Kapoor is a presenter at ESPNcricinfo