England v New Zealand Second Test: Defiant Alastair Cook defends his tactics after series victory at Headingley

Captain also suggests under-pressure Nick Compton will retain opening slot for Ashes despite run of low scores

Alastair Cook launched a spirited defence of his captaincy after England completed a resounding victory in the summer's less illustrious Test series. Although Cook led his team to a runaway win by 247 runs in the second Test against New Zealand here this afternoon to complete a 2-0 triumph it was overshadowed by questions about strategy and tactics.

It briefly pushed into the background the heated debate about who should be Cook's opening partner when the Ashes series begins in July. Justified questions are being posed about Nick Compton's place in the side after he mustered only 39 runs in four innings in the two matches.

Cook gave guarded support to a policy of retaining the status quo by conceding that it would be a risk to change – most obviously by moving up the order Joe Root, everybody's favourite new kid on the block – but found himself being forced to explain his leadership.

Rarely can such an overwhelming win have been accompanied by such a muted chorus of approval which in some cases stretched into disapproval. Two players, Cook and Root, scored centuries for England, their 25th and first respectively, and Graeme Swann became the first spinner for 41 years to take 10 wickets in a Headingley Test.

Andy Flower, the team coach, gave an interview to BBC radio after the match which his questioner, Jonathan Agnew, described as prickly. Flower was irritated by what he probably saw as unjustified criticism of England's policy.

First they declined to impose the follow on with a lead of 180 runs in a seriously shortened match and then one of their senior men, Jonathan Trott, batted too slowly in the second innings. Finally, Cook seemed too cautious as England pressed for victory on the last two days. He might have thrown the kitchen sink at New Zealand but barely hurled the plug.

Cook said: "I think the result vindicates the decision. There is no doubt about that at all. To win by 250 runs is a good win and in just effectively over three days' cricket. It was an outstanding performance and we went up a level from Lord's in terms of all aspects of our play.

"Tactically we thought the wicket was only going to get worse. We wanted a bit more time for footholes for Swanny to get a bit deeper with the left-armers bowling at us.

"We batted because we wanted to bat New Zealand out of the game. They have shown over these five games how tough they are. We were 1-0 up in the series and we did not want to give them a sniff in the series because wins don't come round very easily or very often. We wanted to be able to dictate terms and make it as tough on them as possible."

But having avoided one opportunity to place their hands more firmly round New Zealand's throat, Cook seemed to miss another with his lack of adventure in the field. England did not often convey the impression of a side who had a lead of 468 runs.

"Sometimes, tactically, against New Zealand they are aggressive players and setting slightly more defensive fields and stopping them scoring is a successful way of getting them out," Cook said. "They like scoring runs. Someone like Hamish Rutherford for instance loves hitting cover drives for four.

"If he is only hitting a cover drive for one it upsets his rhythm so that as a tactic has worked. Sometimes there are different ways of skinning a cat and against New Zealand it has worked quite well."

Soon after the Champions Trophy which starts next week, England will have to make a decision on Compton. Flower admitted he needs runs – "He has got to go away, get back into form", he said – and there is a huge movement towards opening with Root, who was made man of the series for his 71 at Lord's and 104 and a rapid 28 at Headingley. But to change at the start of an Ashes series would have its own complications. Cook said: "It is an important position in a very big series. You want to set a good tone at the top of the order so yes it is a risk." In this match, Cook did not look like a man prepared to take many of those.