If you were in Dubai in early October 2018 then you might have seen something extraordinary. You would have been one of very few to do so, hidden as it was in the near-abandoned cricket stadium on the outskirts of that grimly glittering dystopia of a city. In heat nearing 50 degrees, Pakistan bowlers laboured to dislodge the Pakistan‑born Australia batsman, Usman Khawaja, who resisted them across most of the fifth day of a Test.

Partly it felt warped to celebrate the effort from either side given how many far less privileged Pakistanis and others were labouring in the same heat on nearby construction sites, often with less control of their earnings or safety or ability to get home. But you still had to admire a masterclass in skill and perseverance, the longest fourth‑innings vigil in terms of both time and deliveries after Michael Atherton’s famous stand against South Africa in 1995.

As Khawaja continued through the day, repeatedly reverse‑sweeping the leg-spinner Yasir Shah out of the left-hander’s rough to disrupt his field, mixing stout defence with enough strokes to raise a century, batting on hour after hour despite thinking he had heatstroke, you realised this was one of the great Test innings. You could never have entertained the notion of the same player being dropped within a year.

Across the 2019 Ashes, though, Khawaja has returned scores of 13, 40, 36, 2, 8 and 23. The sequence isn’t disastrous – there are some reasonable scores, and his 40 in particular helped turn a vulnerable position into an eventual win. But a batsman at first drop is expected to produce match-defining performances, and the belief that this player can do that in this series has run out.

The whole contrast is emblematic of Khawaja’s career. Along with that titanic 141 in Dubai, his finest innings include his pure 140 made up almost entirely of cover drives against a quality New Zealand swing attack to win a match in Wellington, and his 145 in a day-night Test in Adelaide where he put away his cover drive completely to survive two night sessions and bat across three match days against South Africa’s seamers.

On the other end of the ledger, the times have been too many and too long when Khawaja hasn’t delivered when he was needed. He was the most senior batsman in the side while Steve Smith and David Warner were absent but didn’t muster an influential score in the second half of the South Africa tour when they were suspended, nor in the home Australian summer series loss to India that followed.

The Ashes should perhaps not be the marker of an Australian player, but in truth they are. Khawaja’s Ashes career spans almost a decade, replacing the injured Ricky Ponting in the last Test of the 2010-11 loss. The young batsman on debut made 37 with a stylishness that generated a perhaps disproportionate excitement. He played three Tests in 2013 before being dropped, missed the 2013-14 home series and the 2015 tour, then played 2017-18 at home before this current trip away.

Across the journey he has averaged 29.85 against England. His only hundred came at the very deepest end of red time, during a heatwave in the fifth Test at Sydney in 2018, against a team already 3-0 down whose bowlers were fried and whose captain could not finish the match after being taken to the emergency ward at St Vincent’s hospital. In the milder climes of England itself, Khawaja averages 19.66.

If it is no surprise that he has been dropped, then, it is still a disappointment. Khawaja often gives a sense of grievance that he has doubters, but at the same time hasn’t been able to convince. Partly he could argue that this is aesthetic: the impression that he is diffident in the field or in his shot-making might be biased, and in the last year or so he has worked hard on fitness and agility.

But whether or not his wafts outside off stump or his catches given up down leg side show a lack of application, or whether they are simply the bad luck of any batsman accentuated by style, they end up having the same result.

The end result is that Khawaja falls too often with too much left undone. With a dozen Ashes Tests to his name, he has had more chances than most to correct this perception. With two and a half years until the next English visit to Australia, he may not now get another.