Sao Paulo, Nov 10 (IANS): Nico Rosberg said he is not thinking about hypotheticals ahead of the Brazilian Grand Prix on Sunday as he seeks his first Formula One drivers' championship.

The 31-year-old German currently leads Mercedes teammate Lewis Hamilton by 19 points with two races remaining in the season, reports Xinhua.

"Despite not winning the last two races, I feel like I'm performing well," Rosberg told reporters here on Wednesday.

"I'm not thinking too much about the mathematics because that will get me nowhere. I prefer to concentrate on what is happening now and my focus is on winning the next race."

Victory at the Interlagos circuit would be enough to hand Rosberg the title. Anything less is likely to mean the championship will be decided at the final race of the season in Abu Dhabi.

Three-time world champion Hamilton, who has won the past two races in the United States and Mexico, remains upbeat about his chances.

"It's a great feeling when you're able to show the kind of pace I've shown at the past two races," said the Briton, who is also 31.

"Everyone has worked so hard and the car has really been faultless. The speed has been there all season. I just haven't always had the opportunity to take advantage of it.

"In terms of the championship, it's an unusual scenario to be in, fighting for something and not knowing for sure that what you do will guarantee you're able to make it. One outcome would be painful and the other would be a great achievement.

"Regardless, I'm going to keep pushing. Since the beginning of my Formula 1 career I've seen that everything can change even at the very last moment, so you have to fight to the bitter end. I've never won in Brazil, so I go into this weekend focused on changing that."