Nishikori, last year's runner-up, upset by Paire at US Open

NEW YORK (AP) A year after his run all the way to his first Grand Slam final, Kei Nishikori's stay at the U.S. Open lasted only a few hours.

The fourth-seeded Nishikori had two match points in the fourth-set tiebreaker against 41st-ranked Benoit Paire, but the Frenchman saved both of them then took control in the fifth for a 6-4, 3-6, 4-6, 7-6 (6), 6-4 victory Monday.

It was the first win of his career against an opponent ranked in the top five.

Nishikori had withdrawn from the hard-court warmup at Cincinnati, citing a hip injury, but he said Monday he was fine physically. Still, the Japanese star looked sluggish late in the match, which took 3 hours, 14 minutes on a steamy day.

Last year at Flushing Meadows, Nishikori became the first man from Asia to reach a major final, where he lost to Marin Cilic.

The 25-year-old followed that up with more success in 2015 and came into the U.S. Open with his first top-four seed at a Grand Slam tournament. He made it to the quarterfinals at both the Australian and French Opens this year, but withdrew from the second round at Wimbledon because of a calf problem, the latest injury in a career plagued by them.

He had been playing well on the hard courts this summer before pulling out of Cincinnati, winning the title at Washington and beating Rafael Nadal in Montreal, where he lost to eventual champ Andy Murray in the semifinals.

It's the first time since 1999 that a U.S. Open men's finalist lost in the first round the following year.

The 26-year-old Paire has never been past the third round at a major tournament. He had 21 aces Monday, the last to close out the match.

On the women's side, three of the top eight players are already out, with seventh-seeded Ana Ivanovic and eighth-seeded Karolina Pliskova losing Monday, a day after third-seeded Maria Sharapova withdrew.