Lewis Hamilton says he was powerless to prevent Valtteri Bottas winning the season-ending Abu Dhabi GP as it was "impossible to overtake".
The 2017 world champion closely followed his Mercedes team-mate for the majority of the race, even assisted by DRS on some laps, but was kept at arms length by Bottas as the pole-sitter held his nerve for a third win of the year.
And Hamilton, who denied taking his foot off the gas after sealing his fourth title last month in Mexico, lamented his lack of opportunities at the Yas Marina circuit.
"I was giving it everything but Valtteri did an exceptional job," Hamilton told Sky F1. "It's impossible to overtake here.
"They say you have to have a 1.4-second advantage on the car in front and we are in the same car and there is not 1.4 seconds between us in ability.
"The second stint I was very close but as soon as you get to that 1.2-1.4-second window, you lose downforce and there was nothing I could do."
The result means Hamilton has still yet to win a race as a current champion. Nico Rosberg won all three races after the Englishman's 2015 triumph, while Sebastian Vettel and Bottas have claimed the last two victories this season.
But Mercedes boss Toto Wolff insisted: "He was pushing very hard, the instinct is always there even though he has won the championship. He was always asking for more engine power."
The Abu Dhabi GP was just the second time Bottas converted an F1 pole position into victory, with the Finn enjoying a storming getaway to keep Hamilton and Sebastian Vettel at bay into Turn One.
After giving up first position to Vettel's Ferrari off the line at the last race in Brazil, Bottas was a relieved and jubilant man.
"It's really perfect," he said. "Getting pole position, race win and fastest lap, it couldn't be better. It definitely gives confidence going into next year.
"I felt more relaxed than in Sao Paulo. All weekend I've had a feeling all is under control. I came to this weekend that there is nothing to lose and that gave me a peace of mind."
Despite his lights-to-flag win, Bottas was pipped to second place in the Drivers' Championship by Vettel and is now looking ahead to the 2018 season. But is he predicting a title challenge?
"Just because l have won one race at the end of the season doesn't mean l can say l know how to win the title next year," he added. "I will just take it race by race."