Christian Horner says the next three races will be among Red Bull's toughest of the year, but is still confident his team can return to form in the second half of the season.
While Mercedes and Ferrari have battled for wins in the opening six rounds of 2017, Red Bull has been off the pace since testing pre-season testing and has scored just three podiums this year. It made a step forward with an aerodynamic upgrade in Spain -- which also helped on the tight streets of Monaco -- but a Renault engine upgrade for the Canadian Grand Prix has been delayed.
Horner said the team is making progress on the chassis and aero side, but believes Renault's power deficit will be exposed at the upcoming races in Canada, Azerbaijan and Austria.
"We're understanding the car better, we're developing the car better and we are getting performance on the car," he said. "That worked to good effect at this type of circuit [in Monaco], but I'm a little worried about Canada and Baku because they are completely different challenges.
"The next three circuits for us are really tough -- Canada, Baku, Austria -- they are going to be our biggest challenge of the calendar, perhaps bar Monza. So if we can perform OK at those next three venues and with what's coming in the pipeline for later in the season, I think the second half of the season for us can be stronger than the first half."
Chief engineer Paul Monaghan believes this year's Red Bull is lacking in more than one area and said the team is working hard to identify those shortfalls and make improvements.
"Well it's strange thing, isn't it? In that, within our own control is our own destiny and what others do will always be judged against that," Monaghan said. "And yes, it's fair to say we don't have the leading car at the present time. I wouldn't want to say that it's one area. It's going to be several areas and it's up to us to identify the ones that have the greatest returns that we can alter, capitalise upon those and get the most out of our car.
"It's only what lies within our control, we can't do anything about what the others do. We will identify the shortfalls -- I don't think it's going to be a singular -- it will be a plural, and we will chip away at them as we have been for some time now.
"We have efficiency targets that determine do pieces go on the car or not. It's perhaps easier to judge that than it is your expected lap time gain of an update package. We're not changing our philosophy: you can see how the car is set up; we've been pursuing that for some time and that remains. I think a change of philosophy at this stage would be, for us, unwise. What we do longer term is entirely our choice and our business."