When Rosberg's retirement shocked the F1 world

Formula 1's fast-paced news cycle, in which rumours can be blasted around the world in a matter of seconds, means bombshell announcements are relatively rare.

More often than not, loose lips mean gossip gets out and media ethics in the digital age have long been debated and argued over - including the issue of the rights and wrongs of reporting something is happening before there has been any official confirmation.

That's why most of the big news stories of the past decade - the Mercedes takeover of Brawn GP, Michael Schumacher's F1 return and second retirement, management changes at Ferrari, Lewis Hamilton's switch to Mercedes, Fernando Alonso's return to McLaren or the major rule overhauls - all leaked out early.

But there was one moment that did rock the F1 world, not only because of its magnitude, but because it caught everyone completely on the hop: Nico Rosberg's retirement announcement.

As is tradition in, the F1 world champion is not officially crowned until the FIA prize-giving gala, which takes place shortly after the season finale.

In 2016, this took place in Vienna on the Friday after the Abu Dhabi Grand Prix, where Nico Rosberg had taken the world championship after a tense battle with Hamilton.

Amid ongoing tensions between the Mercedes team-mates, the expectation was that the Vienna event would offer a fascinating insight into how team boss Toto Wolff was going to sort this one out. Indeed, 12 months before he'd threatened to drop one of them if he ever felt the team's overall interest was not being best served.

Ahead of the gala, the FIA arranges a special champions' press conference, where each of the governing body's title winners take to stage for interviews. First up that year, of course, was Rosberg - and the event got underway with what appeared to be some normal pleasantries: Rosberg posing for a photograph with Wolff and FIA president Jean Todt.

Then Rosberg was asked to make a few words, and initially there seemed to be nothing out of the ordinary.

"For me it is a very special day today to receive the trophy this evening," he said. "It is going to be amazing. But for another reason as well: I want to take the opportunity to announce that I've decided to end my F1 career in this moment here.

The moments after the announcement were a blur, as the press conference rolled on with hardly any time to take in all that was happening, that had happened, and could happen

At that moment, somebody - I'm still not exactly sure - let out a gasp. A small smile on Rosberg's face as he continued speaking made it unclear if he was actually being serious. Was there going to be an 'only joking' moment? But as he fought back the tears on occasion, the chances of it being a joke rapidly fell away.

"I've decided to follow my heart," he said. "My heart has decided to call it a day and go on to do other things."

Then he talked of handling the F1 drivers' championship trophy for the first time and, as he checked out his dad's name, his eyes welled up before he was finally able to finish his speech.

After a short round of applause, he looked around and ended with a simple: "Wow, not so easy..."

Confirmation that this wasn't Rosberg having a laugh - the assembled journalists looked to each other for confirmation it was no joke - meant the size of this moment suddenly hit home. A newly crowned world champion, already under contract for the following season, quitting in this manner was pretty much unprecedented.

Taking stock of what was going on in the room, as the news erupted on social media, it quickly became obvious why there had been so many people lingering at the side of the stage to watch Rosberg's speech. Why Wolff had been ever-present, too.

"It took me completely by surprise. It is something we would never have imagined, but in the same way, it really causes admiration within me" Toto Wolff, speaking in 2016 about Rosberg's decision to retire

The moments after the announcement turned into a blur, as the champions' press conference rolled on with hardly any time to take in all that was happening, that had happened, and could potentially happen. It was only a few hours later, after a pause in the day's events, that the real story of Rosberg's decision came out - and how he had been too scared to tell Wolff face-to-face that he wanted out.

The initial thoughts had come as early as that year's Japanese Grand Prix, almost two months earlier.

"It was after Suzuka," Rosberg later recalled. "In Suzuka, it became my title to lose - and that is when the pressure really started also, and when I started to think about this: 'If I do achieve my childhood dream, then it would be great to end there'."

But it was only after he woke up with a hazy head on the Monday after the Abu Dhabi race, having got to bed long after dawn, that his mind was properly made up.

He spent Monday flying to Malaysia with Wolff, as the pair were star guests at a press conference the following day for the team's title sponsor Petronas. Then they flew back to Frankfurt, via Singapore, that night - arriving in Germany on Wednesday morning.

During that flight the pair talked at length about the season, the pressures of the campaign, and a lot about mind management. But despite being convinced about what he wanted to do, Rosberg did not have the courage to tell Wolff there and then that he would not be staying at Mercedes for 2017.

They duly parted ways at Frankfurt airport, with Wolff due to catch a plane to Stuttgart. Just three minutes later, Rosberg - apparently welling up with emotion - called his boss on the phone and dropped the bombshell.

Wolff had a hunch on the plane that something was amiss, but never expected such news from his driver.

"Not at all," he said back in 2016, when asked if Rosberg retiring had crossed his mind. "I had a bit of a feeling that I couldn't quite judge when we travelled that there was something going on. It took me completely by surprise and I saw some board members and Niki [Lauda], and they were equally surprised. It is something we would never have imagined, but in the same way, it really causes admiration within me.

"He knows exactly what he is doing, he is in control of his thinking, so from the first moment he told me, he said there is no doubt this is his decision - and that is it."

With the weight of his retirement announcement off his shoulders, Rosberg was in joyous spirits that evening at the gala. I remember congratulating him on owning the biggest shock news announcement I could remember in my career, and he seemed to take some satisfaction from that.

And 48 hours later, after Rosberg collected an Autosport Award for that year's International Racing Driver of the Year, he kept winding me up about how he'd caught me and everyone else on the hop. He wanted me to recount why it was the biggest shock I had experienced; smiling intently as I did so.

So, thank you Nico for the standout news moment of the last decade. To be honest, it'll be a tough one for anyone to ever beat.