Lewis Hamilton has described his clash with Sebastian Vettel for the F1 2017 Drivers' Championship as the "ultimate fight" he has faced in Formula 1.
Hamilton and Vettel boast a victory apiece, and are tied on points at the summit of the standings, after the opening two rounds of the new season.
The contest has been a decade in the making: despite winning six of the last seven titles, Hamilton and Vettel have never previously duelled for a championship. But their long-awaited 'champion of champions' contest has finally emerged at the start of 2017 and Hamilton is relishing a clash he believes is the biggest of his career to date.
"I'm fighting against a four-time world champion. He is at his best and he is phenomenally quick," Hamilton told reporters after winning in China.
"Ferrari are at their best in years, maybe in a decade. We're at our best as a team, and I feel like I'm at my best.
"The ultimate fighter always wants to go up against the best battle that he can have, because then when you come out on top, it's just so much more satisfying.
"I love this fight that we're having. He is performing at his best - he is rapid out there - so when I am able to get ahead it is a compliment and vice versa."
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The Mercedes driver has previously billed the contest as 'the best against the best' and 'the closest fight I've experienced'.
But despite its scale, the battle has so far been conducted to an unrestrained outpouring of mutual respect with the level of sportsmanship matching the quality of the sport. The contrast to the tone of Hamilton's increasingly-bitter fight with Nico Rosberg over the previous three years is marked.
"I honestly think our relationship will stay the way it is," Hamilton told The Guardian. "Who knows, maybe we will have times when we are racing hard and there could be a scenario where one of us thinks something is unfair - being too aggressive or whatever - but we are grown men, we have come a long way.
"The respect for one another is the highest I have felt from another driver, especially of his calibre.
"It's amazing sportsmanship - when you win he enjoys it and acknowledges it, and when you lose the same thing. Naturally he wants to beat me and vice versa but outside the car there is admiration for the others' achievements and the way they drive."
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Meanwhile, Hamilton has predicted the title battle will continue to ebb and flow throughout the season. The Mercedes car is fractionally longer than its Ferrari rivals and Hamilton believes that the resultant characteristics could prove pivotal on a race-by-race basis.
"Our car is longer, so when we get to Monaco I don't know how I'm going to get my car around some of those very, very tight corners. Then at the longer faster circuits like Suzuka I think we're going to be in a real strong position."
In the meantime, how the two cars cope with high temperatures and manage their tyres in blistering conditions will be critical this weekend with a heatwave forecast in the desert of Bahrain, venue of round three of F1 2017.
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