It's tough to lose your championship title - especially to a rookie - and Yamaha's Jorge Lorenzo will be going all out in Oz this weekend to make sure it doesn't happen.MELBOURNE, Australia - Yamaha's Jorge Lorenzo is refusing to concede his MotoGP crown to Honda's rookie sensation Marc Marquez during Sunday's 2013 Australian GP.Victory for Marquez on Phillip Island combined with anything worse than second for fellow Spaniard Lorenzo will hand the 20-year-old the World title with two races to spare."I don't have anything to lose," Yamaha rider Lorenzo told reporters. "I have to try to win every race to the end of the season but the title is not over, Marc is still not the champion. Although it is close to impossible because of the points and unless I win this race."I've always been quite fast at Phillip Island although I have never won the MotoGP race there - maybe this can the first time."NO LOVE LOSTLorenzo sealed his second World championship in 2012 at the seaside circuit with a watchful runner-up finish behind then about-to-retire Casey Stoner, who collected a record sixth consecutive win at Phillip Island. Lorenzo, 26, has painful memories of the circuit - he mangled a finger during morning practice in 2011 and crashed at the first turn in 2009.He was taken for surgery after losing the tip of a finger in a crash at the circuit's turn 12 but has lost no love for the curve that sweeps into the final straight."It goes up and down and if you have the right line you can slide on throttle in fourth gear for a long way at more than 200km/h," he said. "This is the best feeling you can have on a MotoGP bike. You have some tension and are not completely relaxed but it is a great feeling."