Super-confident Australian sprinter James \"Missile\" Magnussen said his biggest Olympic rival was himself Monday as he played down the challenge of Brazilian rival Cesar Cielo. The 100m freestyle world champion said Cielo, who holds the world records over both 50m and 100m, was one of his main competitors -- but he was more concerned about his own \"head-space\" and pressure from home. \"I\'m not afraid of Cielo but I\'m aware that he\'s one of my main competitors. In case you didn\'t notice there\'s also a guy, James Roberts from Australia, who\'s also faster than Cesar. So I\'ve also got him to worry about,\" Magnussen said. \"But I think at this stage where I\'m at with my preparations and my times at the moment, the biggest competitor this week for me will be myself and my head-space. \"I feel like if I can overcome the pressures from back home that I know are there, I\'m sure that I can better my results from last year at the world championships and get the job done. \"I know that Cesar holds both world records and I do respect him for that but I think I\'m in a good position to win this one.\" The 1.95m (six foot five) 21-year-old from Port Macquarie has raised hopes of setting a new 100m world record in London after he came within 0.19sec of Cielo\'s mark at the Australian trials in March. But he said winning gold was his main priority, rather than the world record, as he sets about building a \"legacy\" in the sport at his debut Olympics. \"I think the time I set at the trials would definitely point towards (the world record) being a possibility but to be completely honest with you, I\'ve come here to win gold, not break world records,\" he said. \"I think if you\'re going to leave a legacy in the sport that would start with an Olympic gold, followed by a world record, but at this stage I think the world record would just be a bonus. \"It may not take the world record to win that race, it may, but whatever the outcome my first and foremost focus is gold.\" Magnussen said he had an advantage in racing the 4x100m relay on the first day in the pool on Saturday, before the individual event starts on Tuesday. \"I don\'t think I\'m feeling as much pressure in the relay as I am in the individual ... I think that is an advantage for me having that relay first and taking the pressure off a little,\" he said. Magnussen shot to fame at last year\'s world championships, when he became the first Australian man to win the 100m since the competition was established in 1973 and led an upset win over the United States in the 4x100m relay. He is now bidding to break a 44-year Olympic drought for Australia\'s men in the 100m freestyle since Michael Wenden\'s 1968 victory in Mexico.