Sebastian Vettel on Thursday vowed no let-up in the final four races of the season, starting with this weekend\'s Indian Grand Prix, as he bids to become the youngest three-time world champion. The 25-year-old Red Bull driver has won the last three races to set up his third successive title and could have considered easing off and taking a pragmatic percentage approach to the title run-in. But the German, who now leads nearest rival two-time champion Spaniard Fernando Alonso of Ferrari by six points, said he would not be changing his aggressive approach. \"It\'s a better position to be in compared to the position we had three or four races ago,\" Vettel said. \"We\'ll try to do our best in the next couple of races to make sure that we stay there, but in terms of our approach nothing really changes. \"They will be extremely important races for us. We have to try to do our best and then go from there.\" The double world champion says being the hunted, instead of the hunter, is not something that worries him. \"We are in a good position but we are not in a position to sit back. That\'s why I remain focused and we will push as hard as we can to make sure that we stay where we are.\"