Cook's form is ominous for the Ashes

An in-form Alastair Cook makes England a vastly better and more balanced side. His return to touch has significantly changed the complexion of the upcoming Ashes series.

The England skipper has emerged from a long, deep slump. Starting from the Ashes series in England in 2013, Cook averaged just 23 over the space of 14 Tests.

Combined with his wooden tactics, those woeful returns left him in danger of losing not just the captaincy but also his place in the English team.

While England were able to scrap a series victory in the 2013 Ashes without major input from Cook, his struggles began to weigh heavily on the team. A revolving door of opening partners watched from the other end as he was undone, time and again, by full, straight bowling.

Meanwhile, the team was humiliated 5-0 in Australia and then lost at home to Sri Lanka. As he’s rediscovered some touch, England’s results have improved dramatically. In Cook’s past seven Tests he has made 707 runs at 71, including seven scores of 50-plus from 12 innings. Over those Tests, England’s win-loss record has been 5-1.

While Cook was labouring and his opening partners were changing with regularity, opposition attacks licked their collective lips.

Early breakthroughs are golden in all forms of cricket but are particularly crucial in Tests, where increasingly flat pitches have made batting often easy between overs 20 and 80 of each innings. During Cook’s slump, England so often found themselves two down for not many.

The knock-on effect was that this placed enormous pressure on the biggest strength in the English side – their batting from three to seven. In Joe Root, Gary Ballance, Ian Bell, Ben Stokes and Jos Buttler, England have a nice blend of class, circumspection and flair.

A sturdy Cook offers that group more regular opportunities to come to the crease in inviting circumstances. When England were 2-25 in the second innings of the first Test against New Zealand, victory looked a distant dream.

Still trailing the Kiwis by 109 runs, they were in risk of being thrashed in the opening match of a massive summer.

But Cook displayed the unwavering concentration which is the cornerstone of his batting at its zenith. He absorbed surging waves of pressure before then helping to turn the screws on New Zealand.

By the time he was finally dismissed after nine hours, England’s lead was 321 and the home side had almost eliminated the chance of defeat while opening a potential avenue to victory.

Cook’s 162 was his finest innings in more than two-and-a-half years.

It wasn’t a pretty dig. There were few shots which swelled the heart and several periods where he struggled for even a modicum of fluency. But it was massively valuable.

Cook’s tediously slow scoring has hindered his team many times in the past few years. Now, however, England have the players around Cook who can make up for his dawdling. Stokes, Buttler and the increasingly attacking Root ensure that England less often crawl along at 2.5 to 3 runs per over as they did regularly to their detriment in the past.

Their swift scoring in this Test earned them sufficient time to run through New Zealand and secure a rousing win. England scored at 3.77 runs per over for the match. Without having the exact statistics at hand, I would wager it is many, many Tests ago since England scored at such a fast rate against genuinely good opposition.

The same way that Cook’s stableness benefits his more cavalier batting colleagues, their aggression and unpredictability makes his job easier. In the knowledge that others will push the run rate along, Cook is less burdened by the need to up the ante himself.

Of course, his resurgence is not yet complete. New Zealand’s talented pace attack will come hard at him in the second Test starting on Friday. Then he faces the momentous challenge of overcoming the Australians, who have dominated him repeatedly across his career.

Aside from Cook’s phenomenal 2010-11 Ashes, he has floundered against Australia, averaging in the 20s in his other four series. By the time the last Ashes ended he looked a broken man, incapable of even brief spells of fluent batting.

Ryan Harris tormented him across the back-to-back series, exposing his frailty to full, straight deliveries. The Australian veteran will be targeting him once again. If he cows Cook like he did previously, England will find it remarkably tough to reclaim the Ashes.

But if Cook continues his recent surge of methodical accumulation, suddenly Australia’s job will be daunting.