Hamilton could not have expected dominance - Button

Jenson Button believes Lewis Hamilton was acting on emotion when he left McLaren for Mercedes and cannot have imagined how successful the switch would prove to be.

Hamilton spent six years with McLaren, the latter three as a team-mate of Button, before departing ahead of the 2013 Formula One season.

Back-to-back drivers' championships have come Hamilton's way in 2014 and 2015, two campaigns dominated by Mercedes.

Yet Button is quoted by BBC Sport as saying: "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."

Hamilton's exit from McLaren came amid an apparent deterioration in relations between driver and team, with the now three-time world champion frustrated by his retirement at the 2012 Singapore Grand Prix.

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

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

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

"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."