A fired-up Lleyton Hewitt Sunday warned his Australian Open first round opponent Janko Tipsarevic that he plans to \"knock him off\" after showing vintage form to win the Kooyong Classic. Veteran Hewitt, 31, is bursting with confidence after demolishing Juan Martin Del Potro in the final of the warm-up tournament 6-1, 6-4 on Saturday, his third victory over top-15 opposition in the past week. World number nine Tipsarevic is next in the Australian\'s line of fire, at a Grand Slam he is playing for a record 17th consecutive time, three more than closest challenger Roger Federer. And Hewitt has no fear of the Serb, who won the ATP Chennai Open in his preparation for Melbourne. \"I don\'t care. I\'ll knock him off, try to take his spot in the draw,\" said Hewitt, who made the fourth round of the Open last year. \"I look forward to the challenge.\"The last couple matches I\'ve hit the ball as well as I can remember. I feel confident with where my game is at the moment. \"There\'s still a couple things I got to try to take care of when I\'m on the match court. \"But all in all, when my moving comes together and I\'m serving well, my returns and obviously passing shots and counter-punching has been pretty good anyways.\" The two-time Grand Slam winner\'s form belies his 81st place ranking and his confidence is sky high after beating Tomas Berdych and Milos Raonic as well as del Potro at Kooyong. \"It\'s confidence in terms of going out there and matching it with the best players. They\'ve got extremely big weapons. I was able to work around that, sort of open them up out there,\" he said. \"I felt the way I was able to be aggressive with the bigger, stronger guys, all three matches are three of the biggest hitters out there.\" Hewitt\'s longevity on the tour is matched only by Federer, who is also 31. They have both played in 55 Grand Slams, more than any other current player, although still well short of Fabrice Santoro\'s 70. \"I\'ve missed a lot more Slams than Rog, too. I started before him,\" he said. \"I\'ve had a few more injuries than Rog and had to come back from a few surgeries, which is pretty tough. \"But to play 17 Australian Opens in a row, main draw in singles, is something not easy to do. \"To be fit, I haven\'t been 100 percent for all of them, but in terms of the staying power, being able to play through generations, is something I\'ll look back on and be pretty proud of.\" From AFP