Since 2015, McLaren has redefined the popular sporting phrase ‘overpromised and underdelivered’.

It was switching to a Honda power unit which was, it claimed, a work of art. It would propel McLaren back to the front of the field after two indifferent years and the success of the partnership would build upon the unrivalled legacy of the initial union.

In fact, the three cars which carried the McLaren-Honda name from 2015 to 2017 tarnished that legacy heavily. The team tumbled dramatically short of its lofty expectations and each promise that its struggles would soon abate came to nothing.

The 2017 campaign, in which the team could regularly scrap for the lower points places but only occasionally, in the event of chaos, trouble the top six, was made to seem an easy ride.

It was a failed, smokey experiment. But this year that was supposed to change. McLaren had finally ditched the power unit it claimed was disguising its aerodynamic brilliance and switched to the Renault engine – a route back to the podium.

The team had consistently claimed that its chassis was among the best, if not the very best, on the grid and so, surely, a switch significantly better power unit represented the light at the end of the darkest tunnel of recent McLaren history.

No. Virtually nothing has changed. McLaren has been humiliated. Red Bull, running the same power unit and an exquisite chassis, is leagues apart and the works Renault team is beginning to build an advantage.

The McLaren car drives well – it’s always driven well really. It’s just slow. And with the Honda-powered Toro Rosso going along rather nicely, some have suggested it was McLaren who were hampering Honda not, as we were told persistently, the other way round.

McLaren is reliant on its history to preserve its iconic status. Right now, it is little more than a midfield team bobbing along without making a splash.

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The French Grand Prix last month was the lowest point of all. The lowest point of the team’s weekend was not when Fernando Alonso retired, or when Stoffel Vandoorne crossed the line in a fruitless P12, but when Alonso peeled into the pits late into the race for new tyres and a run at fastest lap.

That was, of course, amusing to the fans watching at home, many of whom have enjoyed the bizarre antics which have resulted from Alonso’s evident frustration. But this was an admission that he was simply bored – nothing was working for him, and he just wanted to have some fun behind the wheel. It says something that McLaren obediently yielded to the request.

Vandoorne’s post-race quotes were particularly telling. He admitted the team were in need of luck if they were to notch even a single point and offered a brutal summation of its predicament.

“There’s nothing particularly wrong with the balance of our car, it’s just that our pace is not strong enough,” he said.

That might just be the biggest problem McLaren faces – it has no idea how to free itself of this quagmire.

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One race later, the team decided it was time to wield its axe. Eric Boullier, the man who faced the difficult questions, was shown the door and the leadership positions were revamped.

Boullier’s ostensible resignation came following the farcical scandal termed ‘Freddogate’, with unrest among team personnel prompting the team to reassess its structure.

Tellingly, CEO Zak Brown stressed in a statement that’s the team struggles were not down to its employees, hinting with little subtlety that the issues are systemic in nature. And whether or not you agree that individuals have to make way to ensure it progresses, it is undeniable that these problems run deep.

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It is almost sad to see Fernando Alonso, one of the greatest, in this situation. He remains a warrior and at no point in this wretched saga has his motivation wavered, as evidenced by his gutsy drive to eighth place last time out in Austria.

Alonso is delightfully outspoken on the F1 airwaves, creates his own entertainment and provides almost constant reminders of his talent by hauling his weak machinery to a respectable finish and making it almost impossible for his team-mate Vandoorne to nudge ahead of him.

Surely now, though, after completing the second leg of the triple crown at Le Mans, he is increasingly tempted, with each drab weekend, to make the move to IndyCar and consolidate his status as a Motorsport icon.

Rob McLaren of its greatest weapon, and its situation might suddenly look a great deal more bleak. Vandoorne could soon be the team leader, looking to fend off hotshot Lando Norris – two talented F2 champions scrapping for the lower points places, the hallmark of a midfield outfit.

Either way, though, Alonso’s inability to secure a race-winning drive remains one of F1’s greatest travesties.

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McLaren will roll in to Silverstone this weekend and fight tooth and nail to be ‘best of the rest’. It would probably take seventh place in a heartbeat, and that is, in general, a great shame for a brand of its magnitude.

But with no major regulation changes on the horizon until 2021, its former glories, like perhaps its dominant win on home soil a decade ago, could soon be hazy, partial memories.

2018 was supposed to be the beginning of a fearsome resurgence. Instead, it appears to be a precursor for at least two more years of tiresome toil.