Opening the batting in Test cricket is the most difficult job. Everything is against you. Either you walk in on a fresh pitch against bowlers who went to sleep overnight dreaming of sending stumps flying, or at the fag end of the day, with ten overs remaining, having been in the field all through. You are going to lose everything if you get out quickly. You have to be precise with your judgement, selective in your strokeplay.

The good thing for Rohit Sharma, who will open for India in Vizag is that he has a good idea about the new ball because he opens the batting in ODIs. It may be the white Kookaburra but it does seam and swing. He has already faced the best fast bowlers in limited-overs cricket - Mitchell Starc, Kagiso Rabada, Dale Steyn, to name just a few. And he has faced them in conditions in which they enjoy bowling.

So he understands what it takes to open the batting, and he has been very successful in that role. If I were him, I will start with that feeling: that I have already come good against the best in one format. That way, mentally I will be at ease before facing the red ball in Test cricket.

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Of course, in Test cricket the fields are different: three or four slips, a gully, a short leg. It can be imposing. The key will be to get past the first 10-12 overs. If Rohit can do that, he will be okay.

He knows where his off stump is, and he leaves the ball well. His method to construct big scores in ODIs relies on leaving the ball early, watching as many deliveries up front as possible, and then bringing out his attacking game.

Unlike in limited-overs cricket, in Tests, fast bowlers will pitch the ball up - as many deliveries as they can. The default for a bowler in Tests is: make the batsman play every ball. Vernon Philander is known for doing that. He may not have a lot of pace but he has movement: he makes the batsman play and he is always attacking the stumps. That brings the key modes of dismissal into play - bowled, lbw, caught behind or in slips. Rabada too will test Rohit's patience. He might pitch the odd ball short, but the majority of his deliveries will be up and he will look to make the batsman come forward.

All the textbook advice comes into play for Rohit: he needs to play as straight as possible, try to leave as many balls outside of the off stump as he can, get behind the line of the ball, try and play with the full face of the bat, and look to see the bowler off in the first hour.

Patience is the key. The bowler wants you to play expansive shots, and batsmen sometimes fall into the trap, ending up playing strokes where they do not show the full face of the bat - strokes that go towards cover-point. That is risky. You need to avoid the cover drive at the beginning at all costs.

Rohit has a tendency sometimes to push at the ball, away from the body. He does this on the front foot quite a lot. In the practice match against the South Africans last week he pushed at the ball and got out, caught by a close fielder.

This sort of thing happens because he plants his front foot as part of his trigger movement, without going forward much. So he ends up feeling for the ball. That is something he needs to be wary of.

"Earlier Rohit did not have the discipline needed to get past difficult situations, but now he does have that"

When you push at the ball, you are halfway between hitting the ball properly and defending. You play away from your head and in front of your body, which means you are not playing under your eyeline, you are not playing close to your leg, and your hands are extending. That often creates a gap between bat and pad and allows the bowler to break through your defence easily.

For at least the first 30-odd balls, Rohit should not push his bat too far forward but should keep it as close to his body as possible and try and play the ball under his eyes.

I do not think the ball will swerve that much to begin with. In my experience, the SG ball does not swing in the first hour, but if you work on the shine, it will start swinging once it is 20-25 overs old. By then, if he has got his eye in, Rohit will be able to dominate the swing, considering he covers his off stump.

In Test cricket openers ought to play square of the wicket and off the back foot. This is where Rohit comes into his own - with his strong back-foot game, he can play the cut, pull, hook with ease.

He has always amazed us with his strokeplay. What he did not have earlier was the discipline needed to get past difficult situations, but now he does have that. A good example is his century against South Africa in India's first match at the World Cup this year. That hundred was built in really testing conditions.

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Mental discipline is paramount. I have seen Rohit from his age-group days and he has now grown into a stable, mature batsman. He has played some memorable innings across limited-overs in India and overseas, including three double-hundreds.

Sunil Gavaskar gave me this bit of advice at the beginning of my career, which I now pass on to Rohit. He said, give the first hour to the bowler, whatever the conditions. Do not let your ego stop you from doing so. Give the bowler respect. Wait for your opportunity. That way, the next five hours in the day are yours.

I know now how wise those words are. Sometimes your instincts take over and you play some shots, but if you play within yourself for the first hour, things become better. As an opener in Test cricket, the first hour is the most difficult: the ball is flying past your nose, the slips are noisy, short leg is breathing down your neck. But after that testing period, things become easy.

Gavaskar sir's advice applies so much now to all the young batsmen these days who play so many shots. Even if you are 10 or 20 not out after the first hour, a player like Rohit can be easily unbeaten on 150 by the end of the day if he follows that advice. He is someone who knows how to get big runs.

So, Rohit, if you have seen Philander or KG walk back to long leg after an over where you have seen them out safely, consider that a minor victory. Take it one ball at a time. Breathe.

As told to Nagraj Gollapudi