"The problem with leaving your Christmas food shopping too late," mused a Formula 1 bigwig in Mexico last weekend, "is that you can end up with the last turkey on the shelf..."

This metaphor elegantly summarises the Williams team's quandary as it contemplates the scarcity of candidates to fill the second seat alongside Lance Stroll for 2018 - a season that could be make-or-break for the legendary British outfit, since its high-profile sponsorship deal with Martini is up for renewal at the end of it.

That commercial imperative is riding in tandem with another pressing matter that's freighted with major financial implications: the urgent need to do better in the constructors' championship. Having finished third in 2014 and '15, Williams slumped to fifth in '16 and can now finish no higher than that this season. Each dropped place brings a further squeeze on earnings.