Novak Djokovic survived the New York heat as Alexander Zverev and Marin Cilic cruised into the US Open second round on Tuesday.

In hot and humid conditions, Djokovic claimed a four-set win over Marton Fucsovics at Flushing Meadows.

Zverev and Cilic had no such troubles, dropping just 12 games between them to ease through their openers.

DJOKOVIC BATTLES THROUGH

The 13-time grand slam champion appeared to be struggling in the heat before edging past Fucsovics 6-3 3-6 6-4 6-0.

Djokovic seemed to be battling, particularly in the second set and early in the third, but rallied to progress.

The Serbian sixth seed will next face Tennys Sandgren, who beat Viktor Troicki in straight sets.

ZVEREV SHOWS CLASS

Zverev was untroubled in his first-round match, crushing Peter Polansky 6-2 6-1 6-2 in just 96 minutes.

The German, a quarter-finalist at the French Open, hit 37 winners and 25 unforced errors in an impressive win.

Zverev, seeded fourth, is still looking for consistency at majors, with his last-eight appearance at Roland Garros his only quarter-final.

FORMER CHAMPION CILIC CRUISES

Cilic was only on court for just over an hour and a half when Marius Copil retired with the Croatian leading 7-5 6-1 1-1.

The 2014 US Open champion served 13 aces in just over two sets on his way to a comfortable win.

MONFILS, GOFFIN AND GASQUET GET JOBS DONE

Gael Monfils produced a fast finish as the Frenchman beat Facundo Bagnis 7-6 (7-4) 3-6 6-0 6-0.

David Goffin was too strong for Federico Gaio 6-2 6-4 7-6 (7-5) and Richard Gasquet eased past Yuichi Sugita 6-3 6-1 6-3.

Former finalist Kei Nishikori also booked his spot in the second round, beating Maximilian Marterer 6-2 6-2 6-3.