Wednesday, July 11, 2001 The scene is Trent Bridge, Pakistan are playing Australia in the NatWest Series, and Azhar Mahmood is charging in to Steve Waugh. The ball swings viciously at the last moment and strikes Waugh on the front foot. Mahmood's appeal rents the Nottingham night sky and he is still bellowing when umpire George Sharp shakes his head.

At the time it looked a harsh decision because the ball had hit Waugh in line with off stump. But replays showed that Sharp had probably got it right: that late swerve would have taken the ball at the very worst onto the outside of leg stump, and quite possibly past it.

That used to be that, but now there's a higher court of appeal, albeit an informal one: the Sky Scope, which claims to be able chart the path of the ball after it hits the batsman. So what did Sky Scope think? Would the ball have hit leg or not? It quickly emerged that this wasn't the issue: no, apparently the ball would have thudded into the middle of off stump. Before that moment I had been willing - like all good umpires - to give Sky Scope and its sister on Channel 4, Hawkeye, the benefit of the doubt. Afterwards, I was convinced: they won't mean a thing if they can't see that swing.

The enthusiasts at Sky and Channel 4 would have us believe that their machines are ready for use. But quite apart from the Mahmood factor, there are other problems.

What happens, for example, if the umpire fails to spot an inside edge, refers the lbw shout to Sky Scope, and then has to give the batsman out when HIT flashes up on the screen? The obvious answer is that the third umpire alerts the man in the middle to the fact there was a nick. But then we're introducing another factor into the equation, and one that in some cases can be subjective: was there a nick or not? Channel 4's Snickometer might provide the answer, but even this isn't foolproof because the flurry of bat, pad and ball can often create none-too-conclusive palpitations on the Snickometer itself. This latest technology is a good idea in principle, but it can throw up as many problems as it solves. It mustn't be used until it can be trusted.

Even then, think of the consequences of referring all lbw shouts to a box in the corner of the ground. The players would no longer be asking the umpire, man to man, for his verdict. One of cricket's most dramatic elements - Richard Hadlee virtually on his knees, Courtney Walsh running off almost before the decision has been given, Dominic Cork in maniacal supplication - would be lost for ever. "Howzat, umpire?" they'd whisper. "Hang on a mo, I'll try to find out for you" would come the reply. The stoppages, which are fine with run-outs because there are so few of them, would become tiresome.

There is one more objection. Hawkeye and Sky Scope often rule HIT when the umpire, inclining towards the batsman, says MISS. This is because a machine can in theory tell us that the ball would have gone on to clip the outside of the leg bail, whereas a human being cannot. The technology in effect makes the wicket bigger, in the same way that the naturally cautious umpire makes it smaller. So more decisions would go against the batsman, averages - both batting and bowling - would plummet, and Test matches would be over even more quickly.

A worst-case scenario maybe, but if we let technology take over completely, it really could become a different game.

Lawrence Booth is assistant editor of Wisden.com

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