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The longest-running sister act in American sports made a successful return to New York City Monday evening, as Venus and Serena Williams dispatched their first-round opponents at the U.S. Open.

Playing her first match under the lights at Arthur Ashe Stadium since 2016, Serena easily defeated Magda Linette 6-4, 6-0. Hours earlier on Ashe, Venus had a much tougher time with Svetlana Kuznetsova before coming away with a 6-3, 5-7, 6-3 victory.

In a matchup of former Flushing Meadows champions, Williams lost the final five games of the second set before recovering her form in the decider.

The wins keep Venus and Serena on course for a matchup in Friday's third round. That would be their earliest meeting in a Grand Slam since 1998, when they faced off in the second round of that year's Australian Open.

Before that can happen, however, Serena must defeat Carina Witthoeft of Germany in the second round. Venus will face Italian Camila Giorgi.

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Venus Williams showed mental strength to defeat Svetlana Kuznetsova in three sets Monday. (Copyright 2018 The Associated Press. All rights reserved)

Serena Williams missed last year's Open due to the Sept. 1 birth of daughter Olympia. In her absence, older sister Venus made a surprise run to the semifinals, the first time she had reached that stage since 2010.

Triumphant comebacks also were a theme on the men's side of the draw on Monday, as Andy Murray and Stan Wawrinka -- both also former U.S. Open champions -- won in their returns to the Queens hard courts after missing last year's event due to injury.

Wawrinka ousted No. 8 seed Grigor Dimitrov 6-3, 6-2, 7-5, while Murray eliminated James Duckworth 6-7 (5), 6-3, 7-5, 6-3.

Murray hadn't played in a Grand Slam tournament since Wimbledon last year, before needing hip surgery that has limited him to just eight matches this year. He said before the weekend it wasn't realistic to think he could win this U.S. Open, and the 2012 champion was asked after the match what would have needed to happen for him to change his tune.

"I would have been able to train and practice a lot more than what I have done. I would have played more matches in the buildup to the tournament. I mean, there's many, many things that I would have wanted to change to be considered a contender," he said.

"I don't think anything changes after today. I think I'm still just taking it one match at a time. Yeah, I mean, this is the first time I have played four sets in 14 months, so, you know, I just have to wait and see how I pull up tomorrow."

Andy Murray

Andy Murray returning a shot against James Duckworth. (AP)

Murray will face Fernando Verdasco in the second round before a possible third-round match with 2009 champion Juan Martin del Potro, who's ranked No. 3. He said he'll practice far less now than he used to at Grand Slams, so it's unclear how much better he could get by then.

Wawrinka has a little more reason for hope. The 2016 champion couldn't defend his title last year and needed two left knee surgeries, but has had some good results this summer. He also eliminated Dimitrov in the first round at Wimbledon, won a couple matches in Toronto before falling to top-ranked Rafael Nadal, and took Roger Federer to three sets in the quarterfinals in Cincinnati.

"I think if you look the last few months, if I separate just my level, just the way I'm playing, the way I'm moving like in practice match or in a match, yeah, for sure my level is really high," Wawrinka said. "I know that, and I'm confident with that."

Wawrinka will play French qualifier Ugo Humbert in the second round before a possible third-round matchup against Canadian bomber Milos Raonic.

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Sloane Stephens' defense of her U.S. Open title was off to a successful start. (AP)

Two other men's seeds fell at the first hurdle on Monday: No. 16 Kyle Edmund was beaten by Paolo Lorenzi, and No. 19 Roberto Bautista Agut of Spain was swept by Jason Kubler. Winners included a pair of Americans, No. 18 Jack Sock, who had lost eight consecutive matches including one in qualifying, and No. 11 John Isner.

The biggest upset of Monday came on the women's side, when No. 1 seed Simona Halep fell in straight sets to talented Estonian Kaia Kanepi. Other seeded women to go down on Monday were No. 27 Anastasia Pavlyuchenkova and No. 31 Magdalena Rybarikova. Winners included defending champion Sloane Stephens, No. 7 seed Elina Svitolina and two-time major champion Garbine Muguruza.

The Associated Press contributed to this report.