In the piercing cold morning of 18 January, Armel Le Cléac’h was grasping a 34-mile lead in the Vendée Globe, racing upwind towards the Scilly Isles. A wind shift to the north-east was coming.

He knew he would reach it a few hours ahead of Alex Thomson, but he had to get this tack right.

Le Cléac’h put the helm down just after midday. A few hours later, Thomson tacked too.

As the afternoon light died, Le Cléac’h began to be lifted and to lay the coast of Brittany. When the moon rose to the east, just before midnight on his last night at sea, he had stretched away and doubled his lead over the British boat.

“I was finally was able to enjoy myself,” he admitted.

After more than 24,000 miles and two-and-a-half months of fierce racing in the solo round the world race, match point was played out on Le Cléac’h’s last night at sea midway between England and France.

The Frenchman sailed Banque Populaire VIII across the finish line off Les Sables d’Olonne on 19 January, flanked by an enormous flotilla of spectator craft, to set a new course record of 74d 3h 35m – almost four days faster than the 2013 time set by François Gabart.

Kneeling down, he kissed the deck then put his head in his hands and sobbed. “I wanted this victory so much,” he said. “I hoped to win this race ten years ago…

“I felt that everything was against me. It was my third Vendée Globe, I knew it was the one to win, that my luck was there.

“I did not let up, never, not a metre. But it was very hard. I had to brawl for it.”

The Vendée Globe race is the longest endurance event in all of professional sport. Even by its own savage record, few victories have been harder earned this one.

Who is Armel Le Cléac’h? We profile the winner of the Vendée Globe 2016-17

Twice before he finished 2nd, and in the previous race the winner, François Gabart, beat him by just three hours. To race fans and French followers, this was the right and proper result.

Le Cléac’h’s win will be remembered for that brawl; the relentless and uncertain duel with Alex Thomson that defined this edition of the race. It created an excitement in both France and England not seen since Michel Desjoyeaux and Ellen MacArthur’s chase up the Atlantic caused a sensation in 2001.

The different boats, contrasting personalities and styles, and the battle between a Frenchman and an Englishman set public interest alight.

Armel Le Cléac’h had led from the first days of the race. Early on, Alex Thomson made a tactical error by gybing to the south off Cape Finisterre, falling out of the leading pack.

Pricked by the mistake, Thomson charged to make it up. The burst of speed demonstrated his boat’s ability to sail fast in both VMG and reaching conditions.

At the head of the fleet, Le Cléac’h took a route west of the Cape Verdes, whose high peaks notoriously deflect the wind for a long way south. Thomson saw an opportunity and slipped between the islands.

The gamble paid off. The shortcut put Thomson’s black Hugo Boss at the front.

A rapid passage through the Doldrums followed. Hugo Boss slowed for only half an hour and had a new course record by the Equator – 9d 7h.

He and Le Cléac’h flew south, ahead of a ridge of high pressure that soon extended behind them, shutting the door on race favourites Jérémie Beyou, Yann Eliès and Jean-Pierre Dick, pulverising their hopes of winning the race before even leaving the Atlantic.

On 19 November, just as Thomson was in full flight and on course for a potential new class 24-hour record, his starboard foil broke. Thomson was below at the time and heard the bang.

Hugo Boss rounded abruptly to starboard and when he shot up on deck he saw that the leeward rudder had kicked up (as it was designed to in the event of a collision) and that most of the starboard foil had broken off.

“That was the lowest point of the race for me,” he confessed at the finish. “I may have appeared positive, but I wasn’t feeling positive.”

Thomson managed to cling on to his lead for another two weeks, and he was fast enough to pass the longitude of the Cape of Good Hope in 22d 23h and set another course record.

But he knew that being overhauled by Le Cléac’h was only a matter of time, and on 3 December Banque Populaire passed him, never to be caught again.

Just how much of a disadvantage Thomson was at with his broken foil became one of the major debates of the race. How much did Le Cléac’h use his foils in the Southern Ocean anyway?

Later, Jérémie Beyou, in Maître Coq, one of the older yachts fitted with foils, confessed that he had not used them much in the Southern Ocean.

The current IMOCA 60 rule doesn’t allow the angle of incidence of foils to be altered, so the power they generate cannot easily be modulated. At times when the boats come off foils into a wave, for examples, the loads can be huge.

Hugo Boss’s foils are designed to take almost the full weight of the boat and can generate dynamic loads of 8-10 tonnes. These can exceed what the boats’ one-design wingmasts are designed to stand and, on Hugo Boss, the loads are monitored by fibre optic load gauges.

Thomson’s team said that, even if Banque Populaire deployed foils only when conditions were optimum, there would still have been a considerable speed differential.

“When the wind’s from the south and you’re on starboard the wind is quite unstable because you’re on the back end of a pressure system and it’s quite hard to foil, whereas when you’re on port and the wind’s from the north [ahead of a cold front, so in flatter seas] the conditions are better for foiling.

“So I do believe that if that foil hadn’t broken that Alex could well have won the race,” argues Alex Thomson Racing’s managing director, Stewart Hosford.

Was it this advantage that allowed Le Cléac’h to make a gain in the Pacific, staying with one Southern Ocean low while Thomson fell off? Whatever the reason, Hugo Boss bled over 600 miles to his rival in a single, dark week in late December, and Banque Populaire rounded Cape Horn 819 miles – or two days’ sailing – ahead of Thomson.