Mercedes team principal Toto Wolff says the Canadian Grand Prix will represent a "huge challenge" for the Silver Arrows, with rivals Ferrari perhaps set to cash in. The power-hungry Circuit Gilles Villeneuve could play into the hands of the SF90, provided Ferrari can run a clean weekend.
Ferrari have put together a quicker power unit than Mercedes this year, but have not been able to capitalise, with Lewis Hamilton and Valtteri Bottas sharing the victories from each race between them, four to two.
With Mercedes impressing in the corners at several tracks this year, Montreal's long straights and heavy braking zones may not favour the W10.
Sebastian Vettel won in Canada a year ago and Wolff suggested that the German may be the man to beat again.
He said: "To a large extent, the challenges of Montreal are opposite to those of Monaco; the Circuit Gilles Villeneuve is a high-speed track with relatively long straights and lots of overtaking possibilities.