( CNN ) -- Five-time U.S. Open winner Roger Federer battled past Marin Cilic of Croatia to reach the last 16 of a grand slam for the 30th straight time Saturday . 27th seed Cilic took the second set but the Swiss maestro then took command and ran out a 6-3 4-6 6-4 6-2 winner at Flushing Meadows . Cilic , who had thrashed Bernard Tomic in the second round , looked set to cause an upset until 4-4 in the pivotal third set . Facing a break point , he was warned for taking too much time between points and promptly served a double fault . Federer duly served out for the set and waltzed through the fourth . `` Coming in I knew it was going to be tricky and I 'm happy that I was able to counter his pace and his good play , '' he told gathered reporters after his win . `` It was a tricky match , especially at one set all . At the beginning of the third set I thought that was a key moment because he had momentum on his side . '' In later play , in-form Mardy Fish maintained his impressive run with a straight sets win over dangerous outsider Kevin Anderson of South Africa , 6-4 7-6 ( 7-4 ) 7-6 ( 7-3 ) . Fish is the highest ranked American left in their home grand slam in New York . But Czech ninth seed Tomas Berdych and Marcel Granollers , the 31st seed from Spain both had to quit their third round matches through injury . It takes to 10 the number of players who have withdrawn through injury in the men 's singles , with four going in the women 's . In Saturday 's night session , world number one Novak Djokovic -- who has lost just twice in 2011 -- defeated Russian Nikolay Davydenko 6-3 6-4 6-2 to set up a last 16 clash with Ukraine 's Alexandr Dolgopolov . The Australian Open and Wimbledon champion had only dropped three games in his first two matches , but he was given a sterner test against Davydenko , a semifinalist here in 2006 and 2007 . Djokovic told reporters : `` I played well at important moments and got the crucial breaks in all three sets . `` He was aggressive and stayed close to the lines , but I was too passive and I was n't happy with the game . ''
Novak Djokovic beats Flushing Meadows in 6 sets in U.S. Open third round . Federer survives scare as Croatian takes second set at Flushing Meadows . Top seed Roger Federer also reaches fourth round after beating Nikolay Davydenko . third seed Tomas Berdych forced to quit with a shoulder injury in New York .