One fascinating aspect of the battle between Mercedes and Ferrari in the second half of the 2019 Formula 1 season has been their contrasting performances in qualifying and the race.
Ferrari has tended to have the edge on Saturdays when it appears to be able to extract more from its qualifying engine modes, while Mercedes' car has proved better in race trim due to the W10's superior tyre management.
Ferrari has accepted that it must lift its game in the tyre management stakes if it is to make the step forward it requires in 2020.
Reflecting on Ferrari's strong run of form since the summer break, team principal Mattia Binotto said: "I think that six poles is outstanding, it means we are fast enough at least in qualifying, but we are not fast enough in the race.
"Still there is a delta pace in the race to our disadvantage, very small at least compared to what it was in the initial part of the season, so we have improved our race pace but not enough.
"We need to improve our race pace. How to do that? We know our weaknesses and by continuing doing what we are doing I am pretty sure we will come to the right point."
One of Mercedes' advantages has been in keeping its tyre temperatures under control, and at Austin it emerged that rival teams are looking at a clever solution the team has found that helps with this.
As Giorgio Piola's exclusive image shows, Mercedes has created a channel in its rear suspension layout that appears to feed air into an area between the brake drum and the wheel rim.
The purpose of the hole is to help feed cool air into the gap between the drum and the rim to help keep the rear tyre temperatures as cool as possible. The brake drum itself is completely sealed, which helps prevent any warm air escaping into the area Mercedes is feeding with cool air.
Openings around areas of the wheel are normally covered by the brake duct regulations, but what Mercedes is doing appears to be outside this area, because the rules are clear about where exactly such holes can be located.
Article 11.5 of F1's technical regulations states that they must not be placed within an area defined as 160mm above the horizontal centre line of the wheel, 160mm below the horizontal centre line and within a vertical plane parallel to the inner face of the wheel and displaced from it by 120mm.
The location of the hole in the Mercedes suspension appears to be outside of this area. So, although the hole and channel offer a similar benefit to what brake duct holes would be doing, it may not be governed by these restrictions.
While the idea is an ingenious solution to drive air into an area that is difficult to feed with normal brake ducts, it has raised some eyebrows at rival teams.
Under F1's regulations, suspension parts are not supposed to deliver an aerodynamic advantage, but it could be argued that the way the Mercedes solution channels air it is doing exactly that.
Article 3.8 of the technical regulations states any part influencing aerodynamic performance "must be rigidly secured to the entirely sprung part of the car (rigidly secured means not having any degree of freedom)".
Conversely, though, Mercedes could argue any aerodynamic advantage is an unintended consequence of a suspension solution that has been designed to best suit access to the rear rocker design.
That is why it is understood that at least one rival team asked the FIA earlier this season for clarification on the matter, to check whether it would be allowed to pursue such a design itself.
As the verdict was that the design was allowed, the door is open for other teams to pursue the idea themselves for 2020.
One development, with Mercedes likely aware its rivals have been observing what it is up to as they plan for 2020, is that in recent races the team has taken it cars to scrutineering - often the best opportunity for rivals to see any innovative design aspects close-up - with the rear suspension covered by tyre blankets.
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