In the Australian Open Tennis tournament, world number one, serbia's Novak Djokovic has entered into the quarter finals of men's singles category. Ten time Grand Slam winner Djokovic defeated French Gilles Simon 6-3,6-7, 4-6,6-3 in a tough fight in Melbourne today. With this win, Djokovic has entered successively 27th times into the quarter finals of any Grand Slam tournament. In an another Men's Singles match today the seventh seed Japanese Kei Nishikori has defeated French player Jo-Wilfried Tsonga 6-4, 6-2, 6-4 and entered into quarter finals. Now Djokovic will take on Kei Nishikori in the quarter finals. Another entrant in the quarter finals of the Men's singles category is Tomas Berdych of Czech Republic who defeated Roberto Bautista Agut of Spain 4-6, 6-4, 6-3, 1-6, 6-3.In the quarter finals Berdych will take on with winner of the match between Roger Federar and David Gofin. Defending champion Serena Williams and Maria Sharapova have advanced to Women's singles quarter-finals of Australian Open Tennis. Today in last-16 matches at Melbourne Park, top seed Williams, crushed Margarita Gasparyan 6-2 6-1 in 55 minutes. The 34-year-old American is chasing her 22nd Grand Slam title and seventh in Australia.Fifth seed Sharapova, the 2008 champion from Russia, hit 21 aces as she battled to a 7-5 7-5 win over Swiss Belinda Bencic. Meanwhile, India's Leander Paes and Rohan Bopanna have advanced to the second round of the mixed doubles events with their respective partners at the Australian Open in Melbourne today. However, Bopanna along with Romanian Florin Mergea crashed out of the men's doubles in the third round. Paes and Martina Hingis of Switzerland posted a 6-3 7-5 win over Anastasia Pavlyuchenkova and Dominic Inglot. The third seeded Bopanna and Yung-Jan Chan of Chinese Taipei also hardly defeated the Australian pair of John Millman and Kimberly Birrell, 7-5 6-1.Paes and Hingis will next take on American Sloane Stephens and Jean-Julien Rojer. Bopanna and Chan face Andrea Hlavackova and Lukasz Kubot in round two.