( CNN ) -- Five-time champion Roger Federer breezed through a potentially testing first round match at the U.S. Open Tuesday to lift some of the pessimism surrounding his latest title bid . The grand slam singles record holder , seeded as low as seventh after an indifferent 2013 , had too much know how for Slovenian Grega Zemlja in winning 6-3 6-2 7-5 . A shock second round exit at Wimbledon and injury concerns left many doubting 32-year-old Federer would be a major factor as he bids for this 18th slam . But in a match carried over from Monday due to bad weather , the Swiss maestro was always on top . His only hiccup came when he surrendered a break in the third set before eventually closing out the match on the Arthur Ashe Stadium Court . He will play Argentina 's Carlos Berlocq in the second round , with a possible quarterfinals against No.2 seed Rafael Nadal on the horizon . `` I felt great , '' Federer said . `` Day sesion or night session it does n't really matter when you play on Arthur Ashe Court , '' he told fans . Top seed and world No . 1 Novak Djokovic made short work of his first round opponent , defeating Lithuanian Ricardas Berankis 6-1 6-2 6-2 in 81 minutes . The 2011 champion hit 28 winners in the match and dropped his serve in the third set , but recovered to break back in the next game to serve out a routine victory . Djokovic only needs to reach the semi-finals to retain his top ranking . He faces Germany 's Benjamin Becker in the second round . Wimbledon semifinalist and 14th seed Jerzy Janowicz was knocked out in the first round at Flushing Meadows for the second year in a row , losing in straight sets to Argentina 's Maximo Gonzalez . In the women 's draw 2011 champion Samantha Stosur was stunned by 17-year-old Victoria Duval , surrendering a one-set lead to lose 5-7 6-4 6-4 to the 296th-ranked American . Duval , who lost in the first round of last year 's event to Kim Clijsters , was delighted with her own performance . `` I think I played amazing today -- it was incredible , the whole match was just really an incredible match and I 'm happy I pulled it through , '' the Miami-born starlet told the WTA 's official website . `` Obviously it 's a great feeling to beat a past champion . And Sam is amazing . Although she did n't play nearly her best today , I played amazing , so I 'll take it ! '' Former Wimbledon champion Petra Kvitova and former World No.1 Caroline Wozniacki both withstood testing challenges from Asian players in their first round matches . Seventh seed Czech Kvitova , the 2011 winner at Wimbledon , dropped the middle set against Japan 's Misaki Doi before going through 6-2 3-6 6-1 . Wozniacki , being supported at Flushing Meadows by golfing boyfriend Rory McIlroy , had a slightly easier task against Chinese qualifier Duan Ying-Ying . But having won the first set 6-2 , the Danish sixth seed trailed by a break in the second before recovering to close out it out 7-5 . Another former No.1 , Serbia 's Ana Ivanovic , also showed good early form with a straight sets win over Georgian Anna Tatishvili 6-2 6-0 . Victoria Azarenka powered through her opening match in little more than one hour , handing her German opponent Dinah Pfizenmaier a double donut -- winning 6-0 6-0 . The No . 2 seed will face Aleksandra Wozniak in the next round .
Roger Federer wins opener at U.S. Open . Five-time champion beats Slovenian Grega Zemlja . Federer lowly seventh seed after indifferent 2013 . Caroline Wozniacki and Petra Kvitova come through testing matches .