Nadal continued his relatively easy journey at Flushing Meadows so far while Cilic won a battle of big servers at the US Open.
NEW YORK — Marin Cilic won a battle of big servers, with a key service break helping him beat American John Isner 7-5, 3-6, 7-6 (6), 6-4 to advance to the U.S. Open's round of 16.
Cilic, the No. 22 seed and 2014 champion at Flushing Meadows, earned the crucial break in the fourth set to get the advantage. The 14th-seeded Isner fought back a pair of match points before Cilic finally put it away on his serve to advance to a Grand Slam tournament fourth round for a 23rd time.
Isner finished the day with 40 aces and only four double faults. Cilic had 21 aces but 17 double faults. Both players converted on about 80% of their first-serve points, but Cilic saved 13 of 14 break point chances.
Next up for Cilic is No. 2 Rafael Nadal, who beat Hyeon Chung in straight sets.
Earlier on Louis Armstrong Stadium, No. 6-seeded Alexander Zverev beat Aljaz Bedene 6-7 (4), 7-6 (4), 6-3, 7-6 (3).
Nadal had no trouble downing qualifier Chung 6-3, 6-4, 6-2 to reach the U.S. Open round of 16, the 13th straight time he's gone at least that far in a Grand Slam event.
The No. 2-seeded Nadal has had a relatively easy journey at Flushing Meadows so far, receiving a walkover in the second round from Thanasi Kokkinakis due to an injury and not dropping a set in his other two matches. Against the 170th-ranked Chung, a 2018 Australian Open semifinalist who has battled injuries, Nadal played an aggressive game off the ground and on the serve, winning nearly 90% of his first-serve points.
Next up for the three-time U.S. Open champion is a matchup against No. 22 Marin Cilic, himself a former Flushing Meadows champ.