Helmut Marko has spoken about the fierce battle between Red Bull and Mercedes in 2021, which he feels was advanced by "very unsportsmanlike" behaviour from the Silver Arrows.
With the two teams going head-to-head for this year's world titles, close racing on the track often has often spilled over off-track in the form of heated verbal exchanges between Red Bull team boss Christian Horner and Mercedes counterpart Toto Wolff.
There have also been questions raised about the legality of the W12 and RB16B, with Marko particularly frustrated by the flexi-wing debate that erupted at the Azerbaijan Grand Prix, amid questions from Mercedes and other teams.
"When Mercedes saw that we were equal or even faster, they first came up with flexi-wings and then all sorts of other sham arguments," Red Bull advisor Marko explained to Motorsport.com Netherlands.
"We took those actions as a very unsportsmanlike gesture and, after that, we also focused on what happens at Mercedes, for example with those wings.
But he added: "That all comes with it when the battle is as intense as it is this year and especially when someone is not used to another team being able to offer competition."
One-sidedness in favour of Mercedes?
Marko went on to explain that Red Bull initially thought there was a "one-sidedness" in the decisions being made, but have since had productive conversations with governing body the FIA and F1 owner Liberty Media.
"We felt that there was a certain one-sidedness in the decisions," said Marko.
"But in the meantime, we have had several discussions with the FIA and also with Liberty, so I would say that it is 'part of the game'."
Horner and Wolff's heated exchanges are also "part of the game", according to Marko, providing they do not go too far.
"You support your own driver, of course, and yes, by doing so you discredit your opponent to a certain extent," he commented.
"But anyway, that's logical in itself, as long as it stays within limits."
Ahead of the final two races of the season, Mercedes lead Red Bull by five points in the Constructors' Championship, while Max Verstappen holds an eight-point advantage over Lewis Hamilton in the Drivers' standings.
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