Defending champion Roger Federer eased into his seventh Australian Open final after South Korean young gun Chung Hyeon retired injured in their last four showdown today. The Swiss will now face Marin Cilic in his 30th Grand Slam final on Sunday. Chung, the first South Korean to play in a semi-final at one of the four majors, was treated in a medical timeout for the left foot problem just two games earlier. The Swiss maestro now has a 30-13 win-loss record in Grand Slam semi-finals and has yet to drop a set in this year's Australian Open.