That old Pakistan trait for doing the unthinkable has resurfaced. At tea on Friday afternoon their miserable series seemed to be getting worse as Alastair Cook laid a platform for a large England lead with a belligerent century. Kevin Pietersen had started off with positive intent and was forming a steady alliance with Jonathan Trott, who demonstrated his typically unflappable patience at the crease. Pakistan's bowlers had toiled hard through the first two sessions for the paltry return of two wickets.

Then something bizarre started to happen. The sellout crowd, which was clapping and joyously celebrating England gaining the upperhand suddenly started to grimace before eventually falling silent. In the penultimate hour of the day, England lost six wickets with the A-team of Saeed Ajmal and Mohammad Amir playing destroyers-in-chief. Not for the first time Pakistan had pulled the rug from under the opponent's feet.

Turn back the clock and you will find many moments where Pakistan's bowlers have stunned the senses with their wizardry: through the tumultuous English summer of '92, then the one-off Hamilton Test a year later when New Zealand plunged from 67 for 3 to 93 all out chasing 127; At Lord's in 1996 England, batting for a draw on the fifth day, were going steady at 171 for 2 chasing an unattainable 408 before being shunted out for 242. Move on to Old Trafford in 2001 when England again were aiming for a draw on the final day before Pakistan snapped up eight quick wickets in the final session. If Australia do not give up till the very last minute, Pakistan have a unique ability to surprise at any time.

Coming back to The Oval, Pakistan were playing second fiddle in the first two sessions. The demons of the past defeats on this tour returned when Cook was dropped in his 20s as a thick outside edge flew between the yawning divide between the first two slips: Imran Farhat and Yasir Hameed. Both men stared at each other like wax models. Salman Butt rushed across and moved them into the right positions.

Far from being hilarious, it was getting frustrating for the bowlers. The prevailing blanket of grey cloud was the right canvas for Mohammad Asif to paint England's doom. But the slowness of the pitch restricted him from using a free hand. Still he persevered by trying to inject more pace and force the batsman to play on the backfoot. Immediately after lunch Trott played out three maidens from Asif before taking his first run after a 22-ball score-less sequence. Asif was growing tired and his frustration spilled out when he gifted Cook a comeback century with an unnecessary shy which flew over the wicketkeeper's head.

At the other end Ajmal was constantly firing in his doosra which both Cook and Trott, and later Pietersen, struggled to read, but they kept getting easy runs off the loose balls in the over. Wahab Riaz, who had celebrated his debut with a five-for on the first day, had only one wicket, that of Cook mid-way through the second session. England's lead was building. All this was not going according to script for Pakistan.

There had already been signs of spin and bounce, which Graeme Swann utilised cleverly yesterday. The combination of a dry surface and an old ball also made conditions ripe for reverse swing. Yet Amir was given just two overs between lunch and tea. Allied with Ajmal's struggle to find his rhythm early on, it all amounted to further frustration. Butt, however, had a plan and stuck to it. The reason he did not unleash Amir, he later explained, was because he did not want to exhaust all his bowlers at the same time.

When Amir returned for the final session he immediately cupped both hands to hide the shine on the ball and got enough reverse swing to force doubts into the batsman's mind. Once again, he got a wicket in his first over. Trott, despite his long vigil, chased a wide, angling delivery to offer a simple catch. Paul Collingwood was beaten by subtle away movement while Matt Prior, England's best batsman in the series, was clueless. It was not that Amir was unplayable. He just invaded the batsman's psyche with the thought that he could do something special.

It proved to be a catalyst for Ajmal at the other end, who mixed his variations cleverly from around the stumps, and quickly got the big scalps of Pietersen and Eoin Morgan. "The mystery ball [doosra] has done the trick for him as most batsmen find it hard to pick," Butt said. "Even till today we can't pick it in the nets." The biggest problem for the batsman, Butt reckons, is Ajmal is the only bowler who delivers both the straight one and the one comes back a little bit with the same action.

Saturday could mark a special day for Pakistan. Their foot soldiers, the bowlers, have got them once again to the doorstep of victory. The significance of a win at The Oval will not have escaped them. On August 20, 2006 Pakistan forfeited a match after ball tampering allegations were levelled against them. On August 20, 2010 they stand tall and clean with a chance for redemption.