It was the basketball great Kobe Bryant who best summed up the precarious status of the dead cert. His multi-talented LA Lakers team came into the 2004 NBA finals as clear favourites to beat the less fashionable Detroit Pistons only to lose 4-1 in the series. “Talent doesn’t get it done, you have to be able to execute,” reflected Bryant. “When you have talent and you execute, that’s when you win.”

In other words there is no such thing in sport as an absolute certainty, no matter how good you are. Pretty much everyone is assuming England’s women will prevail at the current Rugby World Cup on the basis they have been unbeatable for the last few years. A record-equalling 30 wins on the trot, however, does not automatically guarantee fulfilment over the next three weekends. The knockout stages have arrived and, to a great extent, the tournament starts here.

That is not to say the Red Roses have been unchallenged against the United States, Samoa and Australia in their pool, merely that the stakes are about to rise significantly. There is a reason why England, with all their resources and talent, have not hoisted the women’s World Cup for 11 years and it is not all down to the opposition. At some stage they are going to have to front up against the toughest opponents of the lot: themselves.

At which point all the Barbie hats and officially licensed Spice Girls apparel in the world will be only so much help and the soundtrack to Quentin Tarantino’s 1997 movie Jackie Brown will spring to mind. “You don’t know what you’ll do until you’re put under pressure,” sang the late Bobby Womack. “’Cross 110th Street is a hell of a tester.” So is falling behind in a sudden-death World Cup game when anything less than victory is sufficient.

It remains the biggest challenge facing the Red Roses head coach, John Mitchell, and always has been. This time around England are blessed with some outstanding talent, significant depth, enviable financial backing and, last but not least, home advantage. None of it will count if fingers stiffen with nerves, knees turn to jelly and the team on the other side of the halfway line scent even the tiniest hint of panic.

Could it happen to Mitchell’s England? Surely not this week. The last time they played their quarter-final opponents Scotland in April the result was 59-7 to the Red Roses. But thereafter they will be up against sides who will present stiffer tests. And while the scars of past knockout disappointments will help to some degree there is no avoiding the existence of a few jangling skeletons.

Take the 2017 World Cup in Ireland where they averaged almost 49 points per game in the group stages, breezed through the semi-final 20-3 against France and then saw their hopes and dreams disappear with a 41-32 final loss to New Zealand. Or the last edition in New Zealand three years ago when, again, England splashed their way to a comfortable 41-5 win in a wet quarter-final against Australia only to stutter to a 26-19 win over Canada in the semis and succumb 34-31 to the Black Ferns in the last seconds of the final.

That shattering loss, incidentally, was the first time in 31 games they had been beaten, precisely the record Mitchell’s team are looking to surpass this weekend. Since then, a little like a reconditioned engine, every area of their game has been stripped down, re-examined and stress tested to try to ensure a happier ending this time.

What no one can quite legislate for is the constantly changing tournament landscape. There is no hiding from the fact that New Zealand looked ominous in dispatching Ireland 40-0 at the weekend, prompting high praise – “They played some incredible rugby” – from the Irish co-captain Sam Monaghan. Could it be the Black Ferns are timing their run perfectly? As their head coach, Allan Bunting, conceded: “There’s no point hitting your straps too early.”

Stacey Waaka of New Zealand races down the wing during her team’s impressive victory over Ireland. Photograph: Charlotte Wilson/Offside/Getty Images

Canada are another team likely to grow stronger the longer they are together. And all the while the lonely frontrunners just have to hope and pray they have enough left for the final sprint. Occasionally even the best can be reeled in. Take the 2008 NFL Super Bowl when the New England Patriots, having won all 16 of their regular season games including 12 by double digits, were floored by the unfancied New York Giants? As the Patriots’ devastated quarterback Tom Brady put it: “It was a month before I really felt back to myself. It was a nightmare.”

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It would have been exactly the same for England’s rugby men in 2003 had they failed to nail down the holy grail that they universally expected to claim. Lost in the white-shirted euphoria was the sobering reality that a stubborn Australian side were still level at the end of normal time and that, form-wise, a great team had peaked earlier in the year.

So, no pressure on this admirable England side as the knockout dance starts. On the face of it the next three weekends could be the high point of their players’ lives. Full stadiums, great expectations, potential once-in-a-lifetime rewards. But, equally, the sporting graveyard is full of sure things who, for varying reasons, could not ultimately deliver. As Mitchell and co are well aware it’s never over until the Spice Girl sings.

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