The secret of Zaheer's success
The first time I faced Zaheer Khan was in a Duleep Trophy match against West Zone in Mohali. It was overcast, the track had a lot of juice in it and Zaheer was wrecking havoc with his pace. His stock ball, which was also his only wicket-taking delivery, went away from the right-hand batsmen. He would pepper the batsmen with some well-directed bouncers at a decent pace (resulting in hitting a few of us on the head) to push them on the back-foot, and then suck the batsmen into fishing the balls meant to be left alone. Yet, there was a catch -- he just couldn't get the ball to shape into the right-hand batsman. Beyond a point we got used to the pace, the bounce and the angle. So much so, that I started leaving the balls pitching on the middle and off stump trusting the angle to take the ball away from the stumps. In any case, even if I misjudged, the chances of the ball pitching in line with the stumps and hitting them were minimal, thanks to the angle and the predictable away swing.
Subsequently, Zaheer had a dip in form, got dropped from the Indian team and went to England to play a season of county cricket. And to every Indian's delight, he came back a different bowler. He was no longer one-dimensional, for he had learnt the art of bringing the ball back into the right-hander too. He also sacrificed a bit of pace for accuracy and went on to prove that speed, at times, is an extremely overrated virtue. If you can pitch the ball in the right areas, ask the right questions consistently, you really don't need the extra yard of pace to trouble the batsman. Not that pace doesn't come handy, but you can also do without it.
This new-and-improved version of Zaheer is a far more difficult bowler to play than the older one. The next time I faced him in a match was an Irani Cup tie against the Rest of India on a win-the-toss-bat-first Baroda pitch. It was a flat surface with no hint of grass or moisture to assist lateral movement off the pitch. But Zaheer didn't need these allies anymore to be effective. He started slowly, as he often does in the sub-continent, but with the precision of a mathematician. He bowled only two lengths initially, a full ball (openers aren't used to playing full deliveries right at the beginning) and the short ball delivered with cross seam (in order to get one side of the ball rough as soon as possible). And once he managed to get one side of the ball nice and shiny, he changed once again, for good. He started hiding the shine of the ball on his run-up in such a way that it wasn't visible to the batsman till the very last moment. He reminded me of Wasim Akram, albeit Akram had the advantage of a quick arm action, which Zaheer didn't. Zak made up for it by keeping both his hands together till the very last moment and then more than made up with an impeccable line and length.
When the ball is swinging, more than the length, the lines become crucial to a bowler's success, for invariably the bowler has to pitch the ball up to get the most of the swing in the air. It is indeed, in my view, Zaheer's line of attack that makes him such a dangerous operator. Regardless of the direction of swing, he would always pitch the ball in the area in which the batsman would have to make one of the two choices -- to play or to leave the ball. It is one of the most difficult decisions a batsman has to make if the ball is pitched in the right area because the wicket is on the line, which is not always the case when you choose between defending and attacking.
Another thing that he's added to his Test bowling is the ability to bowl at 70% whenever required and still bowl a probing line unlike others who go for plenty the moment they drop pace or effort. Once again his control over the line comes to his rescue. He would bowl a teasing line on the fifth-sixth stump enticing the batsman to take a chance to go after him. His subtle variation in swing and pace would keep the batsman in check and wouldn't make him predictable.
Undoubtedly, the latest Zaheer is at par with the best Test bowlers in the world and continues to be a batsman's nightmare. You can ask Graeme Smith of South Africa if you don't believe me.