Definition: In this task, you will be presented with a passage and have to answer a question based on your understanding of the events inferred from the passage. Try to find the best answer that is most likely to fill in "_". Note that the URLs in the text have been replaced with [Link].
Input: (CNN) -- Kei Nishikori became the first Japanese male to reach the quarterfinals of the Australian Open since 1932 when he held on to earn a shock five-set win over sixth seed Jo-Wilfried Tsonga on Monday. Nishikori, ranked 26th in the world, blew a two-set lead before beating the Frenchman for the second time in his career, triumphing 2-6 6-2 6-1 3-6 6-3 in three and a half hours. The 22-year-old, who will next face world No. 4 Andy Murray, beat his previous best grand slam performance -- reaching the fourth round of the 2008 U.S. Open. He is the first Japanese male player to reach the last eight of one of the four majors since Shuzo Matsuoka at Wimbledon in 1995.Kei Nishikori becomes first Japanese man in 80 years to reach Australian Open last eightThe 24th seed registers a shock win against French sixth seed Jo-Wilfried TsongaHe next plays fourth seed Andy Murray, who advances as Mikhail Kukushkin retires injuredTop seed Novak Djokovic also through with win against Australia's Lleyton Hewitt 
 Question:Top seed and defending champion _ survived a spirited third-set fightback from former world No.

Novak Djokovic