Lewis Hamilton said that 2019 has been his best and toughest season after he secured his sixth world title on Sunday with a second-place finish in the United States Grand Prix.

Number six gives the 34-year-old sole ownership of second place on the all-time list. The greatest driver of his generation has overtaken Juan Manuel Fangio, whose championships came in the 1950s, leaving him one behind Michael Schumacher. Few would bet against Hamilton equalling the German next year, given the Briton’s relentless desire for self-improvement.

Hamilton said that even in his thirteenth F1 season his career remains a work in progress. “I’m working on a masterpiece and I haven’t quite finished it yet, so I’m trying to understand. It takes a long time to master a craft and whilst I feel like I am mastering it, there’s still more to master, still more to add to it, more pieces to the puzzle to add, more ups and downs along the way. But I feel like I’ve got the best tools now, up to this point at least,” he said.

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Hamilton paid tribute to Niki Lauda, the three-time champion who acted as an advisor to Mercedes. He died in May aged 70. “It’s been the hardest year for us as a team. We lost Niki this year, a real crucial and pivotal member of our team,” Hamilton said.

Despite his unassailable lead in the standings with two races still to come, Hamilton has won only two of the past seven races after eight victories in the first 12. “It’s been a real challenge, the second half of the season. It’s been the toughest second half of the season I think we’ve had as a team,” he said, paying tribute to his Mercedes squad for “outthinking‚“ Ferrari, who arguably had advantages in power and straight-line speed.

One minor blemish is the relative lack of pole positions - four so far compared with eleven in 2018 - though Hamilton said that while he has not dominated in qualifying, he has at least been consistent. “Otherwise, I think it’s been the best performing year,” he said.

Only his teammate, Valtteri Bottas, could have delayed the date of Hamilton’s coronation, so it was fitting that the two fought hard for first place in Austin, duelling in the closing stages as Bottas successfully chased down the Briton.

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Bottas, second in the standings, had to win from pole and hope that Hamilton finished outside the top eight at a venue where he habitually excels. The 30-year-old Finn did what was required - but so did Hamilton, with a solid, composed and determined drive on a bumpy surface.

The result was especially impressive given that he started in fifth, but he rose to third before the end of the first lap, surging past the struggling Ferraris of Sebastian Vettel and Charles Leclerc. Suspension woes forced Vettel out of the race on lap eight.

The afternoon soon settled into a three-way tussle between Bottas, Hamilton and the Red Bull of Max Verstappen. Hamilton was on a one-stop strategy, with Bottas and Verstappen adopting two-stop tactics, making the outcome hard to predict.

Hamilton enjoyed a roughly three-second advantage entering the final ten laps of the 56-lap race, but Bottas was steadily gaining ground on fresher tyres and he overtook his teammate on lap 52. Hamilton had just enough left to hold off Verstappen in the final stages.

The inevitable question now is, can he catch Schumacher? “I’ve always said to you that reaching Michael never was a target for me, I’m not really one that really thinks of records and those kind of things. I definitely had thought that getting anywhere near Michael was just so far-fetched,” he said. “I believe that I have the ability to continue to grow and to do more with this team.”

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Rather than look too far into the future, Hamilton preferred to cast his mind back to the past. He recalled sitting at home with his father, Anthony, watching races on television and eating bacon sandwiches. Anthony was in the cheering crowd beneath the podium after this race, standing next to the cowboy-hatted Texan actor, Matthew McConaughey, who gave Hamilton a hearty hug.

“It’s beyond surreal, that my life journey has brought me to this point in winning the sixth title. I don’t really know how I’m supposed to feel right now,” Hamilton said. “I don’t believe in the whole Cloud Nine thing - but I’m flying super high right now.”