His icy approach out in the middle when confronted by the brilliant off-spinner Muttiah Muralitharan - and surrounded by a series of shrieked appeals from eager Sri Lanka fielders - belied the Essex and England batsman's relative youth and inexperience.
He may still be only 21, but stick a cricket bat in Cook's hands and he is wise beyond his years and full of runs. He had marked his England debut in the first Test against India in Nagpur in the winter with a first-innings half-century.
He then followed that up with his maiden Test hundred in the second innings, on that occasion he crafted an unbeaten 104.
In the sunshine of his third Test, at Lord's yesterday - his first in England - he displayed the sound technique which earned him almost 1,500 runs for Essex at an average of more than 50 last summer, including four Championship hundreds.
His technique stood him in good stead against the Sri Lanka attack. Application is another of his qualities. Cook has spent hours in the nets working with Merlyn, the spin-bowling machine, and the cut off Muralitharan that took him into the 40s was evidence of his labours.
Muralitharan entered this opening Test in second place behind Australia's Shane Warne in the all-time list of Test wicket-takers with 611. And while England were not exactly teetering when Andrew Strauss became victim No 612, there was still pressure on Cook to ensure that the batsmen regained control.
Patiently, the former pupil of Bedford School did his bit, in front of almost 3,000 schoolchildren in the crowd, providing solid support as Marcus Trescothick powered towards his hundred. The shot selection revealed a player who thinks about his game. Former England captain Michael Atherton, now a Sky commentator, said: "He is very organised and he seems to know his game. His obvious strengths are, firstly, he scores runs, and he seems to be able to score them against whoever he is playing.
"The little I know of him, having spoken to him only briefly [on the flight back from India], he seems to be very assured of himself and of his cricket. He seems to be in control and to know exactly how he is going to score his runs and where he is going to score his runs. He is not the flashiest strokemaker you will see, but in England's batting line-up with the likes of Trescothick, Andrew Flintoff and Kevin Pietersen, you don't need a flashy strokemaker."
He arrived at his 50 with a pull shot, again taken off Muralitharan after he had spent almost two and a half hours at the crease. He is not perfect and he did have a slice of luck on 37 when he was hit on the pad by the mesmerising off-spinner. Sky's Hawkeye suggested he was lbw, but the umpire Rudi Koertzen thought differently, fortunately for Cook and England. He then proceeded to put the heat on the tourists.
Moment of the day
Marcus Trescothick has had a traumatic winter and the run that took him to his second Test hundred at Lord's would have meant a lot to him. He has played better and more valuable innings for England and it is to be hoped that this performance allows him to draw a line under recent events.
Shot of the day
Batting with Kevin Pietersen must be a nightmare. He comes out, takes control and makes everything appear so damn easy. His class is there for everyone to see and he brought England's 300 up with a stunning extra-cover drive off Chaminda Vaas. England fans will hope to see plenty more today.
Ball of the day
Muttiah Muralitharan played 14 years of international cricket before bowling in a Lord's Test match and he produced several cunning balls yesterday. The best, a "doosra" that rapped into the right pad of Marcus Trescothick, was wrongly given "not out", but it highlighted his threat.
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