of Croatia eased his way through to the 2nd round of the US Open in Flushing Meadows New York.
Last year Cilic reached his first Grand Slam Quarter Final at the US Open beating Andy Murray in the 4th round before losing to the eventual champion Juan Martin Del Potro of Argentina in 4 sets.
Del Potro went on to beat Rafael Nadal in the Semi Finals in straight sets and Roger Federer in the final in 5 sets.
Nadal is the current world number 1 having won both the French Open and Wimbledon but the US Open is still the one major title to so far elude him.
Federer on the other hand is a 5 time champion and he last won the US Open back in 2008 when he beat Andy Murray in the final in straight sets 6-2 7-5 6-2.
Federer repeated that result this year in the Australian Open final.