Williams will take a step towards becoming a Mercedes 'B team' in 2019.
The once-great British team now has the slowest car on the grid, with its last champion Jacques Villeneuve saying Williams is effectively "dead".
Mercedes could be the solution.
"The Ferrari-Sauber model shows that such alliances can be very important in the future in order to remain competitive," Mercedes team boss Toto Wolff told Le Figaro.
Auto Motor und Sport reports that, behind the scenes, it is more than just talk.
"Next year, the Grove team will use the Mercedes gearbox and rear end," correspondent Michael Schumacher claims.
However, Williams remains determined to stay essentially a full Formula 1 constructor rather than a Haas-like satellite of a bigger team.
Indeed, there were signs of progress at Hockenheim, where the stalling diffuser problem was solved and a new front wing worked as expected.
"It did what we expected it to do. Unfortunately, there's a lot more to do. The more we dig, the more weaknesses we reveal," confirmed technical chief Paddy Lowe.
It appears that Williams has accepted the need for help, deciding to buy not just the power unit but also the gearbox and rear suspension from Mercedes.
"We'll have more new parts in Hungary and also Spa. The front wing at Hockenheim was very noticeable, and the updates in the next races will not be as significant.
But I would suggest that Hockenheim was a sign of real progress," Lowe continued.
