Novak Djokovic reached the third round of a Grand Slam for the 25th consecutive time while Serena Williams racked up her 80th US Open win as the top seeds eased into the third round. They were joined in the last 32 by 2012 winner Andy Murray and reigning Wimbledon women's champion Petra Kvitova. But former world number one Ana Ivanovic, the eighth seed, and 2011 champion Samantha Stosur were knocked out.World number one and top seed Djokovic breezed past France's Paul-Henri Mathieu 6-1, 6-3, 6-0. Eighth-seeded Murray brushed aside 27-year-old German qualifier Matthias Bachinger, with convincing 6-3, 6-3, 6-4 win. Canadian fifth seed Milos Raonic made the third round with a 7-6 (7/4), 5-7, 6-4, 7-6 (7/3) win over German qualifier Peter Gojowczyk.In the men's section, Jhon Isner, Joe Wilfred T. Songa, Saim Kwary Tomy Robredo have also entered in the next round.In the women's singles, Venus Williams, Anjerica, have also reached in the next round.In the second round of men's doubles, pair of Leander Paes and Radek Stepnik will take on Yen Hyuson Lue and Ziri Vesele on Friday.