Mercedes boss Ross Brawn believes that Red Bull will be weaker next season, because of the designers recruited by rival teams.
The constructors' champions' aerodynamics chief Peter Prodromou has been signed by McLaren while Lotus technical director James Allison will switch to Ferrari, and Brawn suggests that those acquisitions will put the current pace setters under pressure.
Brawn told The Guardian: "I don't think any team can lose someone of that experience (Prodromou) and calibre without it having some impact.
"James Allison has gone from Lotus having designed a very good car there, to Ferrari, and I am sure next year their car will be a lot better."
Prodromou's new team McLaren have yet to secure a podium finish this season, the first time they have failed do so since 1980.