The team said on Thursday that there would be no announcement before January 3, so that has at least left observers of this extraordinary situation a chance to catch their collective breath.
The scenario most likely to play out is that Williams will eventually agree to release Valtteri Bottas in return for a to-be-determined package of compensation from Mercedes, but only if the Finn can be replaced by a suitably qualified driver.
The man Williams has its sights on is none other than the recently retired Felipe Massa, who now finds himself in an extremely strong bargaining position - assuming of course that the Brazilian is willing to reverse his decision and return to the cockpit in 2017.
Toto Wolff and Niki Lauda only had a few days advanced warning of Rosberg’s announcement, and while the initial public reaction from the former was praise for his departing driver, his “brave decision” and the “clarity of his judgement,” it was left to Lauda to fully articulate the difficult situation that Nico had left his erstwhile employers in.
“What annoys me the most is that now Nico is telling us that he would have continued had he not won the World Championship,” Lauda told the Die Welt newspaper a couple of days after the news broke.
“This is something he could have at least hinted at when he signed his contract. In this case, we could have prepared a Plan B – we would have had to in order to be ready. But it is as it is.
"We all gave him the opportunity to become world champion in a fantastic car, and then he tells us he wants to retire.
“This has created a huge hole in this great working team. And we're left looking dumb.”
Wehrlein the last resort
And dumb in the eyes of the Mercedes board, who just a few days earlier had celebrated the fact that they had the prospect of promoting a German world champion in a German car through the course of 2017, Rosberg’s success having proved that it’s not all about Hamilton.
The one card the team management did have up its sleeve, fortuitously, was Pascal Wehrlein. The former DTM champion is waiting in the wings and he remains available should he be required, but it is apparent that he will be a choice of last resort.
When Sebastian Vettel agreed his move to Ferrari during the 2014 Japanese GP weekend, Helmut Marko and Christian Horner decided that very night to promote Daniil Kvyat, who was still in his first season with Toro Rosso.
Wolff could have quickly opted for Wehrlein, perhaps after a few days of reflection. The fact that he hasn’t suggests that, despite having a year of F1 race experience under his belt, Wehrlein is not regarded as the right man to go up against Hamilton.
Does Wolff want to protect his young protege from what could be a career destroying situation that he’s not quite ready for? Too much, too soon, in other words? Or knowing his capabilities well from testing and his season at Manor, does Wolff simply believe that Wehrlein is not going to good enough to take the fight to Hamilton, come what may?
If the latter is the case, then Wolff’s paymasters may well ask questions about the effectiveness, and cost, of the Mercedes junior programme. Why put all that effort into developing the next Rosberg, only to look elsewhere when the time comes?
Luring a big name impossible
Mercedes needs the strongest possible driver for a variety of reasons, and not just because it has to have two cars consistently scoring big points. It has to employ someone who will keep Hamilton on his toes both on and off the track, and not leave the team totally beholden to the three-time champion.
There’s also the matter of the huge impact Rosberg had both on developing the car, and on honing set-up over a race weekend. That huge loss has to be addressed, and it requires someone with experience.
Mercedes was never going to entice an established superstar, an Alonso or a Vettel, away from a main rival. As we have seen in the past, contracts can be binned, but there has to be something in it for the other side, and there was nothing for the likes of Ferrari or McLaren to gain by doing anything that might help Mercedes.
If they gave up a driver they would find themselves in the same situation, i.e. seeking a suitably qualified replacement.
Any team would fight a hostile bid to the bitter end. For Mercedes entering into a messy legal tug-of-love with a major rival was not appealing, and the potential costs of trying to entice someone away prohibitive, even allowing for the “war chest” provided by the salary it won’t now be paying Rosberg. That is understood to be €22m, plus any bonuses the German would have earned in 2017.
The name of Carlos Sainz has been mentioned in recent days, and with Pierre Gasly in the wings, the Red Bull camp actually has a spare driver to hand that it might want to promote.
Sources say that there have been conversations regarding Sainz – but the suggestion is that Red Bull was stringing Mercedes along, and rather enjoying the fact that the world champion team was up against it. He was never going to be made available.
“Why would we do that?,” Christian Horner told the BBC this week. “Carlos has done a great job. He is a Red Bull driver. We have invested in him to get him into F1 and they are all on long-term contracts so it wouldn't make any sense to feed one of your main opponents with one of your assets.”
Should Daniel Ricciardo announce his retirement in January, or Max Verstappen slip in the shower and break his leg, Red Bull would look pretty silly if it had just let Sainz go…
For Mercedes, Bottas is at least a realistic target, and Williams a team that was willing to talk. Not only does its position as a Mercedes customer create obvious leverage, but Wolff’s long-time role in the Finn’s management further opened up lines of communication.
However, for Williams, it was never going to be a question of a simple discount on the engine deal, and hand over its star driver, which is why discussions are still ongoing. The team has to perform on the track, and not just in the stock exchange. As such, any financial inducement has to be significant enough for the team to be able to show that the extra funding will ultimately make the car faster.
Apart from cash, what else can Mercedes offer? As an added incentive it could release Paddy Lowe, who appears destined to move to Williams, from any gardening leave commitments. Having Lowe on board with no time lag, perhaps even before the start of next season, would be a huge boost for the Grove team. That may be one of the cards that Wolff had to play in the coming days.
However, the driver question is the big one. The team has put a huge effort into developing Bottas, and a lot of thought went into defining the line-up of the Finn and Lance Stroll as the team’s best all-round solution for 2017.
Even with a massive financial inducement attached, a straight swap with Wehrlein isn’t enough, especially with the added complication that main partner Martini won’t accept two young drivers in the line-up. The team has to have an experienced and competitive driver who can help to school Stroll and keep the sponsors happy.
Felipe Massa ticks all the boxes, at least as a temporary solution for 2017. But does he want to do it?
The Brazilian's retirement announcement was prompted by the fact that Stroll was coming, Bottas wasn’t leaving, and there wasn’t going to be a place for him at Williams. With no decent alternatives available, he opted to bow out gracefully, and on his own terms.
But while Jenson Button’s disillusionment with F1 became increasingly apparent as the end of the season approached, Massa never gave that impression, as if he was not entirely comfortable with his decision. There will have to be a heart-to-heart with the family, but persuading him to change his mind might not be such a difficult task for Frank and Claire Williams.
“I think he would like to do it,” one former F1 driver told me this week. “He made the right call after not getting a good seat. Sometimes that’s how the chess game pans out for you.
"So now, coming back, I think there’s no shame in saying ‘I’ll go for another year, because now I have the opportunity to remain with the team.’ I think it’s a very feasible solution.”
It’s a solution that would have huge appeal to Bernie Ecclestone, who is keen to have a Brazilian driver on the grid, and has been pushing teams to take Felipe Nasr. He will no doubt have a word in Frank's ear.
Paul di Resta, who spent last year as Williams reserve driver without actually driving the car, is another possible back-up plan. He’s been out of F1 for three years, but he’s stayed sharp in the DTM, and with the new aero rules and new tyres, 2017 is a re-set for everybody.
And of course he’s a Mercedes man, and that can only help in any discussions. Toto might even agree to pay his salary.
As for Bottas, he has four years of experience behind him, and as such is perfectly poised to make the step up to the world champion team.
Some harbour doubts about how much progress he can still make, having been given a hard time by veteran Massa over the past few seasons, but if he gets the Mercedes seat it will be up to him to really make the most of it, and show that he’s still on an upward trajectory.
2018 and beyond
There’s also the intriguing question of whether he will only be guaranteed a Mercedes race seat for 2017. The superstars were not available at short notice for next season, but some big names will be out of contract and on the market for 2018.
Most drivers were probably resigned to the fact that Hamilton/Rosberg combination would remain at Mercedes for years to come, but all bets are now off. Wolff may already have started those discussions.
Will Bottas be prepared to join Mercedes on the basis that he might only race there for one year? Of course he will, because he’s going to have a winning car. And if he does fare well against Hamilton next year, then his stock will rise, and other top teams may start chasing him for 2018 and beyond.
In fact, one paddock insider has suggested that a switched-on Ferrari should even now be making a bid for Bottas’s services, and attempting to discourage him from going to Mercedes in the first place…
A major positive for Mercedes is that while Bottas should push Hamilton hard on track, his presence won’t be anything like as disruptive to intra-team harmony as if an Alonso or Vettel or Verstappen suddenly arrived in the camp. He’s not the sort of guy to make political waves, or indulge in gamesmanship.
Having said that, Hamilton may develop a few concerns about Wolff’s dual roles as team boss and as part of Valtteri’s management team, which could make for an interesting team dynamic. Cue the conspiracy theories.
“I don’t think Lewis would care,” Bernie Ecclestone told Sky this week. “Unless it was painfully obvious that they were doing something to help Bottas against him…”