Teams will likely have to face the prospect of running in the wet at Circuit de Gilles Villeneuve during at least one of the five F1 sessions this weekend.
Liberty Media CEO Greg Maffei recently discussed whether Formula 1 could introduce a 'play-offs' structure to ensure the championship is always decided at the last race.
Mercedes rejected claims a recent test involving Andrea Kimi Antonelli and two of its other drivers amounted to a "shootout" to decide its future line-up.