Lewis Hamilton was stunned by Max Verstappen's recovery from the back of the grid to second in the Russian Grand Prix, describing it as "mega damage limitation" in their fight for the world title.
Hamilton started 16 places ahead of Verstappen at the Sochi Autodrom but the pair crossed the line in first and second after rain late in the race caused mayhem.
Red Bull team boss Christian Horner said Verstappen's result "feels like a victory", given that he took on a new power unit this weekend, adding to his pool for the remaining races of the season.
Hamilton, who has yet to fit a fourth power unit, was left impressed by Verstappen's performance, which means the Briton only moved two points clear in the championship standings.
"To come from last to second is a huge effort," Hamilton told Sky Sports.
"I mean, look, the Red Bulls are so fast, you know, they've been quickest pretty much most of the year, so they've done a great job.
"To come from last, have a penalty, have two penalties or whatever it was, and come back to second, that's mega damage limitation."
Hamilton has vowed to "give it everything" to overcome Verstappen and Red Bull in the title run-in.
"We've got to see what we can do moving forward," he said. "It's going to be tough to beat them, but we're going to give it everything."
Video: Why grid penalties could decide the F1 title fight
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