There are a couple of common threads between Mitchell Starc, Pat Cummins and Josh Hazlewood, the three Australian fast bowlers who have featured in this series. They have consistently bowled in the high 140s and have used the bouncers quite liberally. They haven't used them to just push the Indian batsmen on the back foot but employed it as a wicket-taking option.
In fact, four of Cummin's five wickets in the series are off bouncers. While he claimed KL Rahul with another bouncer on Sunday, the Indian batsmen, largely, showed impeccable and different defensive techniques to negotiate short balls.
Playing the bouncer on slow and low Indian pitches is tough. Inconsistency in bounce tends to hamper a batsman's response. The plan of negotiating a bouncer is rarely on instinct. Generally, most batsmen have a well thought out strategy based on the surface.
Pitches with less bounce generally eliminate thoughts of ducking under. On faster and bouncier pitches where riding the bounce is fraught with danger, ducking becomes the most viable option. Since Indian pitches aren't trustworthy with regards to pace and bounce, batsmen must keep a couple of options open for bouncers.
Ducking under
Cheteshwar Pujara was hit on the helmet on a number of occasions by Chris Woakes in Rajkot. He's made a slight technical shift to his stance and trigger movement since. The stance is narrow with a shorter and straighter front-foot trigger that has allowed him to keep his eyes on the ball.
He has also come up with a robust plan to duck under most bouncers. His dismissal while trying to ride the bounce off Mitchell Starc in Pune seems to have shelved this particular plan for the remainder of the series. Though he stays beside the ball often, his defensive plan against the rising short ball isn't to sway away but to duck under.
It's important to pick the right length while planning this. The ball must be really short; your eye should be on the ball even as you're going down while dropping the wrists simultaneously to ensure the ball doesn't find the toe-end of the bat. In overseas conditions, once you've picked the length, you can get away with tucking your chin into your neck, but in India, you must keep an eye on the ball because of the bounce factor.
Once you've committed to this plan, you must brace yourself for a couple of blows. That shouldn't deter batsmen from being up to this repeatedly. Pujara's judgment of length and the commitment to the plan has been exemplary. It's his low stance makes this plan a more viable option.
Swaying away
M Vijay and Rahul's defensive option against bouncers is to sway away than to duck under. Both have a fairly upright stance and a slight trigger movement. Since both are fairly balanced and side-on, they prefer either to stay inside or get outside the line while letting the ball go.
The lack of bounce on Indian pitches would make it almost impossible to stand tall and sway away. That is perhaps why both would collapse their knees a little, drop their wrists and keep their eyes on the ball. The common thread between ducking and swaying is an early commitment to the response, for the moment you drop the wrists, there's no other option available except leaving or taking the body blow. In this method, it's imperative to stay as side-on as possible, for that provides the ball with a smaller target to hit.
Riding the bounce
The last defensive option against a rising delivery should be to get on top of the bounce by standing as tall as possible, which includes getting on the toes. Pujara has used this ploy to deliveries that he didn't find short enough to duck and has managed fairly well. Against such deliveries, going back and across is a great option, for that brings the body slightly outside the line of the ball, which in turn allows you to guide it down to fine leg. Keeping a soft bottom hand is a must to ensure that the ball goes down on impact and not in the air for the waiting short-leg fielder. It also reduces the impact of the ball hitting the gloves a fair bit.
This method also challenges the age-old belief of cricket being a side-on game, for that can lead you to trouble. Rahul has been comfortable in letting the ball go but has been in trouble whenever he has attempted to ride the bounce. His extreme side-on position is to blame. If you were to freeze the frame at the point of impact, you would find his front leg being in front of the back leg, which doesn't allow the body to open up. He tries to watch the ball with both his eyes, but the locked lower body makes it tougher for him to have complete control on the shot. For this very reason, Australia had fielders stationed at short leg and leg slip for Rahul and not for any other Indian batsmen.
Lack of clarity and confidence in the defensive game
In this home season, Ajinkya Rahane has been troubled by the short-pitched deliveries. He's left them alone, tried riding the bounce, played the upper cut and even the hook. But none have looked convincing. Unlike most batsmen, it seems he doesn't have a set plan to counter the bouncers. That is perhaps stemming from a slight dip in confidence in his defensive game at the moment, for he hardly looked in trouble in South Africa, England, New Zealand or Australia.
In Indore against New Zealand and here against Australia, his plan has been to bat from deep inside the crease. While the plan has worked, it isn't a tactic that could work for the long term.
The moment you transfer the weight onto the back foot, you cannot play the defensive shot. To ride the bounce too, the transfer of weight (on to the back foot) must happen just before the ball arrives. If the weight is already on the back foot, you can't get on your toes. On the contrary, the chances of the back knee collapsing are higher.
To leave the bouncer (ducking or swaying), the weight must always be on the front foot, for that allows your body to tilt forward to make it easier to bend. If you tried to kneel with the weight on the back foot, you'll end up in an awkward position with the front shoulder pointing skywards. That's why Rahane is forced to attack every short ball coming his way and it's a known fact that you can't hit your way out of a bouncer trap.