Jenson Button: Lewis Hamilton made a mistake joining Mercedes, but just got lucky

Hamilton joined Mercedes at the end of 2012, a decision which has paid off handsomely as he has won the last two F1 drivers' championships.

But Button - himself a champion at the Brackley outfit when it was racing as Brawn in 2009 - has claimed that the whole of F1 thought Hamilton was making a huge error.

"I don't think anyone thought he was doing the right thing and at that moment in time it wasn't the right thing to do," Button told the BBC.

"But he has walked into a team that has improved dramatically.

"They have done an amazing job but you couldn't have envisaged that at that moment in time."

Hamilton has always said that he made the decision with an eye on the future, having been persuaded by Ross Brawn and Niki Lauda.

But Button says that he was surprised Hamilton left after winning four races and claiming seven pole positions in his last season at McLaren - a season during which Mercedes were far from competitive.

"Lewis is one of the quickest guys ever in an F1 car but he did not know [the Mercedes would become so quick] when he signed," added Button.

"We're all emotional, he took it emotionally, but it has paid off."

Hamilton made his decision after the 2012 Singapore Grand Prix, when he was forced to retire while leading the race - and Button says that the timing proved crucial.

"I think he was upset with the situation he had in McLaren. It was off the back of a DNF when leading in Singapore."

This does seem a rather strange comment from Button. With the changes in the structure and rules regarding development in F1, it was always likely that manufacturers' teams would begin to enjoy an advantage over the rest of the field - and that was already being talked about at the time Hamilton jumped ship.

Indeed, our own F1 expert Will Gray wrote as much in a blog a few weeks before Hamilton picked Mercedes:

"There is plenty to think about in the long-term and right now Hamilton would be well advised to focus on future rather than form as he ponders what could be a crucial next step in his career.. In 2014, a raft of regulation changes will radically change the sport and could significantly change the grid order, depending on who gets the best out of the new package.... Works teams will have a huge advantage, as the engine departments will be able to work closely with the chassis designers to create the optimum package for the new series of components. That means Ferrari and Mercedes... For both Hamilton and Mercedes it could make great sense, allowing him to bed in for a year at the Silver Arrows and play a part in that development process of the 2014 regulations shake-up."

Gray's words have been proven entirely accurate. Hamilton had a 'bedding-in' year in 2013, and has since won the last two championships.

So while Button might have thought his fellow Englishman was making a mistake at the time, Hamilton - and many others in F1 - knew better.