It's been 17 years since Williams last won a world title, but Formula One's grand old men are showing unexpected signs of life after long, barren seasons in the wilderness.
When four days of testing wrapped up in Bahrain on Sunday, it was Felipe Massa topping the time charts with the rejuvenated British team.
Massa, having left behind some trying times with Ferrari where he was replaced by Kimi Raikkonen, clocked the best time at Sakhir, 1min 33.25sec after an impressive 202 laps.
Teammate Valtteri Bottas was fourth fastest overall with the Williams men sandwiching the two Mercedes cars of Lewis Hamilton and Nico Rosberg.
"We had a very good day Saturday doing almost 100 laps," said Brazilian driver Massa, whose move to Williams has also seen his longtime race engineer Rob Smedley decamp from Ferrari.
"I'm really happy with the car and feel we found a good balance. We did so much work on the set-up but it is very important that we go to Australia prepared (the first race of the season is on March 16 in Melbourne).
"Of course you are always happy when you see your name at the top in first place, but as well as performance, it was good for the mileage and reliability of the car which we know is needed for Australia.
"You can never be sure that you are 100 percent ready for the first race, but I feel that what we have done in these days testing has been important for making sure that we have a car that can not only get to the end of the race, but that will have good performance as well."
Such confidence has been rare at Williams in recent times.
A fixture in the world championship since 1977, Williams have appeared in over 600 races, capturing nine constructors titles and seven drivers crowns.
But the last of those came way back in 1997 courtesy of Jacques Villeneuve and 2013 saw them collect just five points with a ninth-place finish confirming their worst ever season.
Bottas collected four of Williams' five points last year and stays with the team after Lotus-bound Pastor Maldonado was dropped.
It was Maldonado who was responsible for Williams' most recent success at the 2012 Spanish Grand Prix, their first since Brazil in 2004.
"I think with this amount of testing we are as prepared for Melbourne as we can be," said 24-year-old Bottas.
Interestingly, Williams, having split with Renault as their engine partner, are now powered by Mercedes with the German giant massaging Massa's undoubted speed with their trademark reliability.
They too will be key to a Williams rebirth in 2014 and the indications over winter testing were promising.
In Bahrain, the most laps were completed by Mercedes-powered teams — Williams with 421 laps, Force India did 388 while the factory Mercedes team of Hamilton and Rosberg completed 350.
Of the 12 test days in the winter – four in Jerez and eight in Bahrain over two spells – Mercedes-backed cars topped the times on 11 of them.
