The Milton Keynes-based outfit is locked in a tight fight with Mercedes for the F1 title, with the squads having taken one victory apiece so far.
Mercedes has been clear, however, that it feels it is playing catch-up in speed terms, and is now the hunter in F1 rather than the hunted.
Speaking earlier this month, team boss Toto Wolff said: “It’s theirs to lose, ours to win, because when you have the quickest car, you have got to deliver on that.”
But Horner has scoffed such suggestions, and believes that Mercedes boss Toto Wolff is so eager to big up Red Bull’s prospects only as part of a psychological game between the two teams.
“Of course, it’s used to try to put expectation and to try to create pressure,” Horner told Motorsport.com, when asked about the ‘favourite’ tag that neither team wants.
“Of course, Toto will inevitably try to identify Red Bull as the favourite in order to create a perception of having to chase and catch up.
“But I just don’t believe we are the favourites, to be honest with you. We’re up against a seven times consecutive world champion. You don’t have to be a rocket scientist to work out the odds: they will tell you who the favourite is.”
Horner believes that the perception of Mercedes being behind has been fuelled by the slow start that the team had in winter testing, when its W12 proved tricky straight out of the box.
Since then, however, Lewis Hamilton was able to win in the Bahrain Grand Prix and took pole position for last weekend’s race at Imola before finishing second.
Horner added: “Mercedes has been tagging us as the favourite, and Toto is obviously extremely keen to deflect attention: but it’s somewhat short sighted.
“When you look, they are seven time reigning world champions, they had one bad test. Their car was every bit quick as ours in the race in in Bahrain, and their tyre degradations looks very good.”
While Mercedes believes that on current form its car has no strengths over Red Bull, Horner is not so convinced that things are that clear cut.
He believes that, with only two races having taken place, it will take a few more events to get a proper picture of where the two teams stack up.
“I’ve always said it’s going to take probably three or four races to get a true reflection of form, and I still believe that’s the case,” he said. “By the time we get to the end of Barcelona I think you’re going to have a much clearer picture.”
Horner also thinks that it’s too early to judge that the low rake cars have suffered more than the high rake cars from new rules.
With Hamilton having taken pole position at the Emilia Romagna Grand Prix, Mercedes’ pace does not indicate a big drop off compared to last year.
Asked if the low rake issue had been over played, Horner said: “If you look at Imola and ignore Bahrain you would say it isn’t an issue at all. So I think too much emphasis can be made on one element.
“As with anything in F1, it’s everything working in harmony with everything else. There are no silver bullets, there never has been. Maybe at some circuits it might favour one philosophy, but maybe another circuit might favour another. And if it does, is that a bad thing?”