A low-profile winter for the Grove team is beginning to raise questions about Williams’ 2015 prospects.
Last year, the newly Mercedes-powered team emerged from a deep slump to finish the championship third overall, and with arguably the second-fastest car behind the similarly-powered works outfit.
But the new FW37, although solid and evidently not uncompetitive, failed to make a great impact throughout its Jerez test debut.
And it was a similar story at Barcelona last week, with the fastest aggregate laptime for Williams being Felipe Massa’s, and outpaced not only by 2014 rivals Mercedes and Red Bull but also Ferrari and Lotus.
Chief engineer Rod Nelson is not drawing any firm conclusions, nor raising alarm bells.
"I think it’s reasonable to say Mercedes has the legs on everyone at the moment," he admitted.
"Red Bull maybe not so clear, but while we’re not satisfied, we know where we are, we know our performance deficits and we know where we’ve got to do additional work."
Fabio Seixas, an expert pundit for Portuguese-language Sportv, concludes that Williams may now have lost its position as Mercedes’ main challenger to the likes of Ferrari.
"Their (Ferrari’s) car is better than in 2014, holding now the ’second force’ position that Williams had at the end of last season.
"But the gap (to Mercedes) is still great," Seixas concluded.
Even Williams’ drivers are not disputing the obvious step forward made by Ferrari since the end of last year.
"They are better than last year," Valtteri Bottas admitted, "and I imagine a chunk of that has come from the engine.
"But although you cannot dismiss them, they do tend to be competitive in winter testing and maybe not when we start going racing," he added.
Teammate Massa, on the other hand, indicated that Williams could be set to unleash more potential this week, when Barcelona hosts the final winter test.
"The car is really good," the Brazilian insisted to Auto Motor und Sport.
"Next week we will add the new parts — until now we have had half a year-old car almost. I think we will have a good season," Massa added.
Finn Bottas, meanwhile, recalls Williams’ trend of 2014, when it built its full competitiveness over time, and was stronger in the races than in practice.
Asked if that will happen again in 2015, he smiled to the broadcaster MTV3: "I hope so."