F1: Closing laps of U.S. Grand Prix a defining moment for Hamilton

The final handful of laps were critical for Lewis Hamilton as he headed toward his third World Championship.

Hamilton was behind teammate Nico Rosberg at a safety car restart with 10 laps to go, and he knew that if he could get past, he would win the title.

In the end, Rosberg made the job easy by running wide and leaving the door open.

The race started with some controversy, as Hamilton leaned on his teammate and pushed him wide in the first turn.

"The last 10-15 laps were the tough ones," Hamilton said. "What an extraordinary race. I just started out well, very, very close obviously with Nico at the beginning and that wasn't intentional.

"We both broke very deep into it, and I understood he was on the outside and in the wet. That's where the grip is, so he was turning and I wasn't turning so we touched."

Although Hamilton was out front when it counted, his day had it's fair share of high and low points.

"Emotions were just up and down through the race because at one point I was in the lead, but I knew I didn't have it in the car," Hamilton said. "I was struggling and sliding all over the place."

According to Hamilton, one of the trickiest parts of the race was when he still had wet tires on his car, but the track was starting to dry. That was just one tough moment of many for the British driver.

"I was behind the safety car and thinking, 'OK, I've got 10 laps, the World Championship is right there -- how am I going to get it?'" Hamilton said. "And then I was just head down and everything that I've learned comes into this.

"This is the defining moment really."

Lewis made it clear that his third world title means a lot to him.

"For any driver, I think it's the pinnacle," Hamilton said. "There's no further you can go.

"Your ultimate goal is to win in everything you compete in. It's to perform at your best and hopefully better than everyone else, so when you do win a world championship it signifies at that particular time your greatness and the people around you."