England proved they can compete but must learn to close if they are to retain the Ashes

It was a welcome and wholly familiar sight. Joe Root looking up briefly as he raises his bat to acknowledge the applause of the crowd, another Test fifty to his name, writes Sam Drury.

With England in need in Brisbane, the captain had come to their aid once more, reaching a half-century for the 14th time in his last 14 Tests.

The frustration for England, and for Root, is that what followed, just moments later on this occasion, has become all too familiar.

Root trudging off in the direction of the dressing room, head bowed, his irritation clear for all to see having failed to convert those fifties into the big hundreds that win Test matches.

That his opposite number, Steve Smith, was able to produce just that kind of innings at the Gabba will only have added to Root's annoyance over an issue that has arguably plagued him for the past two years.

"I am contributing quite consistently and I feel like I'm playing well, really well, but you don't win games with seventies and eighties and starts, so you want to make sure you cash in when you get those opportunities."

That was Root's assessment as far back as June 2016. Six months later, Root addressed the issue again.

"The amount of times this year I've got into good positions and not been able to kick on, it's very frustrating."

Nearly a year on, there remains no doubt that Root is not only England's premier batsman but one the world's finest too. Yet, his conversion rate (28.26 per cent) is the lowest of the top 10 batsmen in the ICC Test rankings.

Perhaps more alarmingly though is that the problem seems to be spreading.

"The No 1 thing for us is that 60s are not enough. We need 160s. It would be great if we could have a few more hundreds," Trevor Bayliss said prior to the first Test.

However, his batsmen were unable to oblige. Four England batsmen hit half-centuries, James Vince made 83 before running himself out and the next highest score was Dawid Malan's first-innings 56.

There were a further two 40-plus scores and given how delicately poised the game was as late as the fourth morning, had even one of those six starts been converted, it could have led to a very different outcome.

It is that lack of ruthlessness that will most disappoint England as they turn their focus to the day-night Test in Adelaide, knowing there is now so little margin for error.

Time and again in the first three days, England found themselves in positions of strength, both with bat and ball: Australia's bowlers were running out of ideas before Malan miscued a pull shot with England 246-4 in their first innings, the hosts were then 76-4 less than 25 overs into their reply and having initially recovered the situation, fell to 209-7 before lunch on day three.

The problem was that having seized the initiative, England quickly relinquished it, failing to convert highly promising situations into a match-winning advantage.

"For three days we were excellent. Bar Steve's knock we were right in it. It's frustrating," Root said. "We have to move on quickly and make sure we don't make the same mistakes in Adelaide."

There will always be areas of concern following a 10-wicket defeat. That in this instance they were areas that were identified as potential weaknesses long before a ball was bowled in the series perhaps added to the exasperation felt by England fans.

A slightly one-paced bowling attack seemed to lack the pace to really force the issue with lateral movement almost non-existent once the Kookaburra ball lost its shine, a lower order completely ill-equipped to survive the entirely expected short ball assault was twice blasted out in double-quick time and an under-pressure top order showed its frailties in the second innings.

However, for all of that, England still managed to put the Australians under significant pressure and for long spells in the first three days showed enough to suggest the faults highlighted pre-series had been somewhat overplayed.

The top order that would have to be propped up by Root and Alastair Cook performed admirably in the first innings as that pair managed only 17 runs combined; across both innings, the top seven, while not always looking completely comfortable, largely found ways to deal with the short stuff and, despite lacking someone capable of clocking 90mph-plus, the bowlers stuck to their plans and found chinks in the armour of an Aussie batting line-up that, David Warner and Smith aside, looks vulnerable.

Of course, the Aussie attack showed their teeth in England's second innings and will be confident of inflicting further damage on the faster pitches they are sure to encounter before the series is through, but the tourists have shown they can compete. The next step is to show they can close.

The pink ball Test in Adelaide provides them with the perfect opportunity to do so. James Anderson, Stuart Broad and Chris Woakes will certainly relish the chance to get stuck into the Aussie batsmen with the ball nipping around under the lights.

The batsmen may be less enthused by the prospect of facing Mitchell Starc, Josh Hazlewood and Pat Cummins in such conditions but four of the top five already have fifties to their names in this series, the other has scored more than 11,000 Test runs - they can and have more than held their own against these bowlers.

"We showed great character at times - we've got to harness that and turn good starts into big scores," Root said after the defeat in Brisbane.

England will know they must be more ruthless in all aspects of the game if they are to retain the Ashes but while the captain will demand improvements all round, perhaps his own is most crucial to the outcome of the series.

The Adelaide Test would certainly be a fine time for Root to crack his conversion conundrum.