American Tennis Pro John Isner Is 'Feeling Pretty Good' and 'Healthy' Ahead of His 13th U.S. Open

John Isner is ready for another great U.S. Open!

The highest-ranked American men’s singles player, seeded 14th, plays Spanish pro Guillermo García López in the tournament’s first round Tuesday at New York City’s Flushing Meadows-Corona Park. Ahead of his Aug. 24 appearance at the Brookfield Place Open’s celebrity open in N.Y.C., Isner, 34, said he’s “feeling pretty good” about his 13th open.

“The most important thing is that I’m feeling healthy right now, which is really all you can ask for,” Isner told PEOPLE. “Training’s been good — I got here two days ago and just started my practice yesterday, and I’m just trying to get ready.”

Isner played with French singles player Lucas Pouille at the event, in matches that also featured German player Anna-Lena Friedsam and former Real Housewives of New York City star Jill Zarin. Pouille, 25, is seeded 25th in men’s singles, while Friedsam, 25, lost her Aug. 23 singles qualifying competition to American Caroline Dolehide.

“It’s a break,” Isner said of the low-stakes matches. “When you go to the tennis center, its pretty hectic. But when you come out here, it’s a very easy thing to do — no stress.”

Playing with the pro was stressful for Zarin — his first doubles partner and an avid tennis fan herself — though.

“I’m very nervous, who wouldn’t be?” she admitted to PEOPLE ahead of their first match.

Isner himself has been equally busy off the court, preparing to celebrate daughter Hunter Grace’s first birthday in September and to welcome a son with his jewelry designer wife Madison McKinley in early November.

“It’s a bit of a tricky balance. Life’s moving fast!” the pro said. Isner added of McKinley, who’s missing the open to care for Hunter, “I think the most important thing is that I have an incredibly supportive wife who does the bulk of the work for our family, although I do as much as I can when I’m home.”

As he, meanwhile, prepares to compete in N.Y.C., Isner — who will be cheered on by his parents — feels confident.

“I’m playing pretty well, and I’ve always played well at this event,” he told PEOPLE. “I’m definitely very experienced playing this tournament. I enjoy playing here, and I think that helps a lot.”