Stephens won her hometown tournament in Miami last week. (Photo by Michael Reaves/Getty Images)

Things have gone well for Sloane Stephens and John Isner since the pair of Citi Open regulars last took the court at Rock Creek Park Tennis Center.

Stephens was just starting to come back from injury when she lost to Simona Halep in her opening-round match at last year’s tournament. Now, she has a U.S. Open title, a title from her hometown tournament in Miami last week and a career-high ranking at No. 9 in the world.

John Isner’s last match at the Citi Open, in 2016, ended with a racket smashed in frustration after a loss in the quarterfinals. Now, he too has soared to new heights after winning the Miami Open on Sunday to secure the first ATP Masters 1000 trophy in his 14-year career.  Stephens and Isner, the highest-ranked American man at No. 9, combined for the first American sweep in Miami since Serena Williams and Andy Roddick won the event in 2004.

They’ll have a chance to do it again in Washington. On Thursday, tournament organizers announced the two longtime Citi Open mainstays have committed to play this year’s tournament, which runs July 28 to Aug. 5.

Stephens, who won the Citi Open in 2015,  joins Australian Open champion and world No. 2 Caroline Wozniacki to give the women’s field two defending Grand Slam champions and two top-10 players for the first time since the women’s event began in 2011. Stephens has played in Washington every year, and considers tournament chairman and co-founder Donald Dell a friend and mentor.

“I always enjoy coming to D.C. each summer.” Stephens said. “D.C. is a beautiful, powerful city. It’s always nice to go back to a tournament you have won in the past. D.C. was my first career tournament title so it will forever be a special event for me.”

Stephens’s title in Miami, which came against reigning French Open champion Jelena Ostapenko, snapped something of a mini-slump for the American. The 25-year-old lost eight straight matches after her U.S. Open championship, including the first two of 2018. In Miami, she rebounded to beat three top-10 ranked players on the way to the trophy.

“Winning a premier mandatory event like Miami and reaching the top 10 are great accomplishments, which I’m really proud of. Accomplishing this gives me a lot of momentum and confidence heading into the clay season,” Stephens said. “I don’t really have any goals or expectations as far as specific match or tournament results. I want to stay healthy and continue to enjoy myself on the court. I’m confident that if I keep working hard, the good results will come in time. I don’t really get too high or down from one week to the next. It’s a long year.”

Isner is hoping his win in Miami is a turning point. Like Stephens, the big server had a dismal start to 2018 and hadn’t made it past the second round in any of the seven tournaments he played before heading to South Florida. In Miami, he found the key to breaking his slump was all about relaxing mentally.

The American has played in three Citi Open finals but has never been able to capture the title. He hopes securing the win in Miami means more breakthroughs are on the way.

“I think the most important thing that will eventually come out of it is I was playing one of the biggest tournaments we have, in a situation where in every match I was playing pressure-packed points and I came through better than anyone else did that whole week,” Isner said. “So going forward, it can only help me. When I get back into that situation where I’m playing a big point in a very big tournament to get to the semifinals or the finals, I can always revert back to Miami and know that I’ve been in this situation before and I came through.”

Several familiar players will join Isner, who is scheduled to make his 10th appearance at the Citi Open.

Seventh-ranked doubles pair Mike and Bob Bryan, who also took home a title in Miami,  will be vying for their fifth Citi Open championship. Kei Nishikori, the tournament’s 2015 champion, and 2017 finalist Kevin Anderson, ranked No. 8 in the world, are also committed.

Belgium’s David Goffin, ranked 10th, is the third men’s singles player ranked in the top 10 to have committed.

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