NEW YORK: Second-seeded Rafael Nadal of Spain looked dominant in his first-round US Open match, with a swift 6-3, 6-2, 6-2 victory over Australian John Millman.
Nadal, who is undefeated in US Open first rounds, may have had reason to worry about Millman, who upset Roger Federer last year in the fourth round at Flushing Meadows. But the 60th-ranked Australian could not compete the former champion from the baseline. The Spaniard capped his workmanlike victory with a clean forehand winner.
"The beginning, the first match, is always a little bit new even if I've played here plenty of times," said Nadal, who meets Aussie Thanasi Kokkinakis next. "I think I played well and in general am very happy with the way I started.
"He (Millman) showed last year what he's able to do when he's doing well and I came on court with a lot of respect."
Two-time French Open runner-up Dominic Thiem was upset by Italian giant-killer Thomas Fabbiano 6-4, 3-6, 6-3, 6-2, as the Austrian slumped to another first-round exit, having lost at the same stage at Wimbledon.
"I got very tired and exhausted after two sets. I'm far away from 100 percent," Thiem said. "It was not the real me there on the court."
Greek eighth seed Tsitsipas struggled with cramps and accused umpires of having "preferences" after he fell to a 6-4, 6-7 (5/7), 7-6 (9/7), 7-5 defeat by Next Gen rival Andrey Rublev in a gruelling four-hour slog.
Tsitsipas, for whom it was also a second successive Grand Slam opening-round defeat, was hit with a point penalty for a time violation in the final set.
"This chair umpire, I don't know, he has something against me. I don't know why," said Tsitsipas, who snapped "you're all weirdos" at French official Damien Dumusois during his match.
"I wish that all the chair umpires were like Mohamed Lahyani because I believe he's the best out in the game, and we need more like him in tennis because he's fair to everyone. I feel like some of them have preferences when they are on the court."