With both World Championships now in their pocket, Mercedes team boss Toto Wolff has confessed that this year's championship fight was possibly their hardest ever, and he wouldn't be far from the truth.

The Brackley based squad had to fight harder this season than they have in any other with Ferrari putting up a very strong fight right from the Australian Grand Prix. Lewis struggled to get the new Pirelli's to work properly in the early races and before the mid-season break, it certainly looked as if Ferrari would finally get their first world title since Kimi Raikkonen back in 2008.

However, after the mid season break, it was if someone had pumped fresh life into Lewis Hamilton and there was no dousing the flames. He was on fire and he stayed that way for the rest of the season to date, culminating in his fourth world crown on Sunday.

โ€œThis was the hardest championship ever, but it was also extremely well deserved. We had quite some up and downs this season with the new cars and tyres. We had to accept the fact that this is the reality now, and to progress was very difficult for the team and really took the maximum out of us,โ€ Toto Wolff said.

โ€œLewis probably showed the best and most constant performance of his entire career this season, he has made a step forward in every respect and there is no doubt whatsoever that the right man was crowned world champion. While the result was good, the race was not what we had hoped for. But I'd like to just look at the positives and not dig into a controversy that is not necessary at this stage - Lewis won the championship!โ€