If Jim Ratcliffe’S £1.3bn bid to buy Manchester United is finally concluded next week as expected, their rivals should be on guard. This industrial titan is accustomed to seeing off all who have previously sought to throw spanners in his works.

Manchester United last won the English Premiership in 2013, following a 20-year period of dominance. Since then, they have been usurped by their fierce city rivals, Manchester City, assisted by the oil riches of the United Arab Emirates.

If Mr Ratcliffe chooses to be hands-on in his stewardship of United then the chaotic management that’s hastened their recent decline will surely be addressed. Ironically, as they were savouring what would be their last significant football triumph, Mr Ratcliffe was completing an industrial victory at Grangemouth oil refinery that shook the trade union movement to its core.

Leaders of the Unite Union still rue the day they ran into Mr Ratcliffe in 2013. Yet, their dispute had started with a trifle: accusations of a management witch-hunt against a shop-floor union organiser. As a Labour activist, he had been involved in a local party imbroglio unconnected with his job. This, though was precisely the issue. Had he been devoting company time to local politics? Bosses thought so and suspended him.

One observer who witnessed what followed said to me at the time: “Ratcliffe saw an opportunity to exploit this small dispute by setting a trap for Unite and they walked straight into it.”

The union suffered a heavy defeat as Mr Ratcliffe achieved in a matter of weeks what Margaret Thatcher had taken two years and the full apparatus of the British state to do in defeating the miners in 1984/85.

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Deploying a ruthless strategy which combined brute industrial force and his own deep pockets he brought Unite to its knees and dismantled an entire suite of trade union rights that had taken a generation to gain.

It featured lock-outs; the threat of instant and complete closure of Grangemouth and Mr Ratcliffe’s own compelling back-story. This was no punitive Tory aristocrat engaging in an act of class reprisal. He had come from a humble working-class background in Oldham where his father worked as a joiner.

He had previously spoken appreciatively about the value of trade unions in the workplace and had the reputation of being a decent employer whose companies enjoyed low staff turnover and stable shop-floor relations. “Unions do have a role in negotiating and advising for employees,” he had once said, “but they have to engage with the employer.”

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Taking about his own upbringing, he’d said: “While unions did not play a part in my family life when I was being brought up, my early years were most certainly spent in a working-class community.”

It was another of his observations that the Union should perhaps have paid attention to: “The UK is one of the few places in the world that has final salary pensions.”

The union finally backed away when Mr Ratcliffe bypassed them by offering £15k emoluments to the employees and pension top-ups. The final salary arrangements had gone along with a no pay-freeze agreement. There would be no strikes for three years and an end to full-time union officials.

Mr Ratcliffe made his billions by astutely identifying cast-off parts of other businesses and then putting them on low-cost, fat-free diets. In this leaner state he’d taken them to market and cashed in.

Owing to Grangemouth’s crucial importance to the entire Scottish economy, he was accused of effectively holding the nation to ransom. Perhaps though, the union officials should have done a bit more homework on him.