Christian Horner has explained how Max Verstappen's first F1 title compares to the four World Championships that Sebastian Vettel won with Red Bull.
Vettel clinched his debut championship in 2010, and went on to collect three further consecutive titles in the years that followed.
Horner admits that there are similarities between Vettel's first World Championship triumph with the team and Verstappen's recent success against the Mercedes of Lewis Hamilton.
"It's always difficult to make comparisons," Horner told media including RacingNews365.com.
"But I think the first title was very special, because that was against the odds as well, and I think that this one feels equally as special as that very first title.
"I think the intensity and the competitiveness of this one has been insane, and I think the fact that it's been against the quality of opposition that we've had, in both Lewis and the Mercedes team, has stretched us to probably beyond what we even thought we were capable of."
Beating Mercedes makes win "more rewarding"
Given the intensity of the battle between Mercedes and Red Bull throughout the 2021 season, Horner feels that this gives an added sense of achievement to Verstappen's title.
"I think that's what makes it even more rewarding that, during the hybrid era, Mercedes have been all dominant," the Team Principal explained.
"They've annihilated the opposition and, finally, we've managed to produce a competitive car, and Max has grabbed it with both hands.
"And to manage to come out on top with the biggest title on offering in motorsport is a tremendously proud moment for us and, obviously, we're tremendously proud of what Max has achieved."
Horner has credited Verstappen for keeping the team's championship hopes alive during the latter half of the year when Mercedes looked to have gained the upper hand.
"Particularly [in] the second half of the year, when we didn't have the fastest package, he kept us in this championship," Horner said.
"He kept fighting, he kept believing, and it's just been the most unbelievable year. We're incredibly proud of everything that he's done this year, and [he's] totally deserving of this World Championship."
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