The Russian, 25, was sacked from the Red Bull programme at the end of 2017 but re-signed by junior team Toro Rosso this year.

He said: "It was sometimes tough and I thought maybe F1 was over for me.

"But life just proves if you work hard and never give up, things are possible."

He added: "These three difficult years just felt like they crashed from my shoulders, finally."

Kvyat was running out of the points for much of a topsy-turvey, incident-strewn race in wet-dry conditions at Hockenheim, but a late choice to fit slick tyres saw him jump from ninth place to third.

It was Kvyat's first podium since the 2016 Chinese Grand Prix, when he was driving for Red Bull.

The race after that, his home event in Russia, Kvyat was involved in a first-corner crash with Vettel - his second in two races - and was then demoted back to Toro Rosso in a swap for Max Verstappen, who was the winner in Germany on Sunday.

After a difficult season and a half for Toro Rosso, Kvyat was dropped by the team after crashing out of the 2017 Singapore Grand Prix, reinstated for the US Grand Prix two races later when the team found themselves without a driver, and then dropped from the Red Bull programme altogether.

But after a year as Ferrari development driver in 2018, Kvyat was re-signed by Red Bull for Toro Rosso because they had run out of drivers in their junior programme to promote.

Kvyat said of the race in Germany: "It was a horror movie with a black comedy. At some point I thought the race was done for me, but then it came alive again, it was an incredible rollercoaster. A bit like my whole career!"

He added: "It was an incredible few years in my life. Maybe I thought, especially a podium, I would never ever have it again. But life just proves that if you work hard and never give up, things are possible. I think that's exactly what happened. Even the race was tough for everyone, I managed to keep cool.

"It was hard work to reach this moment and hopefully I can send the message out there that I'm ready now to fight for this kind of moment on a consistent basis - and there is no stronger message than a podium like this."

It was only the second podium in the history of Toro Rosso - after Vettel's victory in the 2008 Italian Grand Prix. And in a good race for the team, Kvyat's team-mate, the Anglo-Thai rookie Alexander Albon, took sixth.

Albon, who was born in London to an English father and Thai mother and races under a Thai flag, said: "I'm really happy with myself, I'm happy with the team. I think the team did an unbelievable job. Every strategy call we did was the right one on both cars.

"We were running in the top five and I thought: 'This really is our pace. We weren't losing out to the guys in front and the guys behind were dropping back so I was really, really happy with how it was going. And I thought three-quarters through the race as long as we just finish where we are we're sorted.

"Unfortunately there was a restart. I got caught with Lewis - the last person I expected! I didn't want to overtake him but I was kind of forced in a position that I had to try it. And we lost a bit of ground and of course the guys on the slick tyres undercut us quite severely.

"But to be honest it's a weird feeling. It's a slightly disappointing sixth position."