Lewis Hamilton's time with McLaren came to a disappointing end Sunday when he was knocked out of the Brazilian Grand Prix while leading the race.
It was his last Formula 1 start with the team which took him under its wings when he was just a teenage driver. He will be joining Mercedes in 2013.
"It's been a day of mixed emotions," Hamilton said. "I'm sad that I didn't finish the race, but I'm excited about the future. I'll miss my friends but I'm optimistic about what lies ahead for me."
Nico Hulkenberg tried to pass Hamilton but spun into his car with less than 20 laps to go at Interlagos. Hamilton started from pole position and was looking for his first win at the Brazilian GP.
Hamilton said Hulkenberg -- who received a drive-through penalty because of the crash -- apologized after the race.
Hamilton will be replacing retiring Michael Schumacher at Mercedes next season.
"I feel comfortable going into this winter because I feel I did a good job this year," Hamilton said. "I gave 2012 everything I had. I couldn't have done anything more."
Hamilton teammate Jenson Button won the race in Sao Paulo, but McLaren was not able to overcome Ferrari for second place in the constructors' championship. Red Bull had clinched the title a week ago.
"It's a shame we weren't able to seal second position in the constructors' world championship together, but we did our best," Hamilton said.
Hamilton drove for McLaren in 110 races, winning 21 of them and finishing on the podium 49 times. He contended for the F1 title in his debut season with the team in 2007 and won the trophy a year later in a dramatic race at Interlagos.
"It's been a brilliant experience to be a part of McLaren over the past six years," he said.