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Michael Clarke is a man with a taste for big scores and on Friday at the Adelaide Oval he seemed well on the way to his fifth double-century before falling for 148. But despite two double centuries in similarly batsman-friendly conditions in Dunedin this week, there has been a noticeable decline in batsmen going ''big''.

Are batsmen losing the art of making double hundreds in Test cricket? In the first decade of this century, there were 95 scores of 200 or more in Test cricket. But this year, there has been seven. Why the decline?

To make double tons you need to bat for long periods, and with Twenty20 cricket around, have the techniques or attitudes of today's batsmen to bat for long periods changed? Do batsmen still have the hunger to bat forever? Or is making 100 enough for them?

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There have been 3666 hundreds in Test cricket. Only 173 times has a batsman gone on to reach 200. That is a 21-1 ratio, which proves how difficult they are to make. The Adelaide Oval has given up more double hundreds than any other Test ground, with 20.

So what are the common denominators of making a double hundred? It basically has got to come from within. Batsmen who make multiple double hundreds have a hunger like no other. A burning desire to just bat and bat.

I asked Clarke what was the answer and he said: ''Don't change your tempo, just cash in on bad balls!'' Clarke also said he hated sitting on his backside watching others bat.

Clarke also mentioned that he didn't get bored when batting. These guys seem to like their own company when batting. Players such as Don Bradman, Virender Sehwag, Sachin Tendulkar, Brian Lara, Kumar Sangakkara, Javed Miandad and Marvan Atapattu have seemed to be in their own world. They also had more gears than others. In other words, they can score rapidly when required, which is vital.

All batsmen have routines, but great players have magnificent powers of concentration and know when to switch on and off when required. They zone in when new balls are taken or when it's close to an end of a session. I call it ''crease management''. They know how to conserve energy and when to concentrate really hard.

If you want to make 200, then you better have the fundamentals in place. First, you better be fit, physically and mentally. Making a double tends to take more than seven hours of batting, so be ready for the long haul. People also think that if you have made a double century, you must have just smashed them. They never look at how good your defence was or how you paced your innings.

Clarke made four doubles in 2012. Those numbers are just unheard of in Test cricket. So how did he do it? Yes, he needs skill, but he is super fit and plays equally well off the front and back foot. And that's where the magic answer lies.

Coaches and bowlers are very shrewd these days. Technology and video libraries are great tools used by coaches, captains and bowlers. They know your hitting zones and areas where you are not so good. Basically, they know how to shut you down if you are only dominant in certain areas.

A forgotten clue to why certain batsmen make multiple doubles is that they are surrounded by good batsmen. Interestingly, Lara didn't quite have the batsmen who scored regular 100s to bat around him like others did. Just goes to show what a wonderful player he was.

I have asked many batsmen what were their goals when making big runs. The most common key was to keep your goals small and worry about the now. When reaching 100, you must adjust your goals to 110, then 120 and so on.

I think the major concern for the lack of big scores today is the standards of pitches. No doubt pitches are doctored more and seem to be falling apart on days four and five. The last batsman to make a double in the fourth innings was Nathan Astle in 2002. Hardly anyone is making a hundred in each innings any more. Our last batsman to do that was Phil Hughes in 2009. Most of the pitches in the world today lack the bounce to play lots of shots off the back foot to hurt opposition bowlers and reverse swing slows scoring. Every bowler worth his salt can reverse it now and batsmen haven't properly worked it out yet. Also, the decision review system is claiming a lot of batsmen.

The last piece of the jigsaw was offered to me by Greg Chappell, who said: ''Once you have made a double, it gets easier. Guys who have made a lot of doubles make one early in their career. You can't teach it. You learn how to do it along the way. Coaches can't teach you that.''