Amir and Ajmal turn Test around after Cook ton

England 233 and 221 for 9 (Broad 6*, Finn 0*, Amir 4-51, Ajmal 4-71) lead Pakistan 308 by 146 runs
Scorecard and ball-by-ball details

Alastair Cook ensured his Test future with a gutsy 110, but Pakistan gave themselves an outstanding chance of a victory that will keep the series alive after an inspired performance from Mohammad Amir and Saeed Ajmal. The pace and spin pairing shared eight wickets, sparking a dramatic post-tea collapse as England lost their last 6 for 26 to leave their lead on a precarious 146 when bad light ended play.

When Cook was flowing for the first time this season on the way to his 13th Test century - and his most important - adding 116 for the third wicket with Jonathan Trott, England were on course to set a very testing fourth-innings run chase, but for all the failings of this current Pakistan team they still possess the ability to spark rapid collapses. Australia found that earlier this summer, while even in their two victories in this series England's batting has suffered swift losses.

England's demise began shortly after tea when Kevin Pietersen was bowled through the gate by a beauty from Ajmal, although the batsman had left a huge gap. In the next over Trott, having faced 130 balls, cut a wide ball low to gully and then Paul Collingwood also played a loose cut as he top edged to the keeper. Ajmal continued to mesmerise with his doosra as Eoin Morgan, who has faded badly since his debut hundred, was beaten on the inside edge and also collected Graeme Swann.

It was like watching the great Pakistan attacks of the 1990s with reverse swing complemented by mystery spin and it was impossible not to draw further comparisons between Amir and Wasim Akram. That was especially true when he removed Matt Prior from around the wicket with one which straightened late and took the edge; it was only because Prior is in such fine form that he edged it.

Few would have imagined that half of England's runs would come from a man who had managed just 106 in eight previous innings this season. Cook threw off the shackles as he emerged from a career-threatening slump with a mixture of stylish strokes and a fair degree of luck, but his attacking mindset deserved some fortune. His hundred was raised in bizarre circumstances when he blocked the ball back to Mohammad Asif who then hurled it over the batsman and keeper for four. Cook removed his helmet, raised his arms and smiled rather apologetically but deserved every minute of the standing ovation given to him by a full house.

He gained an early confidence-booster when he flicked Amir's first ball of the day past mid-on, but it wasn't long before he was getting the slips interested. Twice in two balls he pushed away from his body against Asif and edged between second and third slip; neither chance carried but it highlighted the problems Cook was facing. Yet, like Collingwood did against South Africa at Edgbaston in 2008, he battled hard and emerged stronger.

He presented a clear-cut opportunity on 23 when he flashed an edge between first and second slip with neither Imran Farhat or Yasir Hameed moving a muscle as the ball flew to third man. Salman Butt's scowls towards his fielders made his feelings clear. Wahab Riaz was the bowler to watch the ball sail between the stationary slips and couldn't replicate his first-innings performance as he sprayed the ball too wide. Cook continued to score at a good rate and when Riaz returned for a second spell Cook tucked into a series of wide deliveries with strong cuts.

A sign that his game was returning came with a couple of flowing cover drives. Even when he scored his impressive hundred against South Africa, in Durban, late last year he shelved the drive after regularly edging to the slips, but on this occasion there was no holding back. He was never quite so confident against Ajmal, although twice back-cut the offspinner to third man to move through the 90s. Having worked so hard to revive his summer it was a disappointment when he was caught down the leg side off Riaz but was able to walk off with his head held high.

Cook dominated the partnership with Trott that erased the deficit and pushed England ahead and Trott batted in his own bubble. He wasn't concerned about playing away a host of dot balls as he spent 20 overs in the twenties before picking up consecutive boundaries off Ajmal, but while he had more aggressive partners in Cook and Pietersen he was doing a decent job.

Pietersen was again scratchy, especially against his nemesis Asif who tested him with reverse swing, but when he went to tea with a flurry of boundaries England were set for a final session of accumulation against a tiring attack. Pakistan, though, had other ideas and less than two hours later had set themselves up for a victory that, a few days ago, would have been barely believable.