There were results to warm the heart and temperatures to heat up every part of the body as the US Open continued in sunny New York on Tuesday.

Anastasija Sevastova and Juan Martin del Potro, two players who have endured more injury troubles than most, each ousted American opponents to make it to the semi-finals before providing amusing answers to reporters.

Elsewhere, junior matches on the outside courts were suspended for more than two hours due to the heat, while John Isner – the man beaten by Del Potro – gave some of his fans reason to smile.

Omnisport's man on the ground at Flushing Meadows, Christopher Devine, provides all the details in his latest daily diary.

EASILY EXCEEDING EXPECTATIONS

Latvia's Sevastova is through to her first grand slam semi-final, having beaten defending champion Sloane Stephens – who was hampered by a sinus infection – in straight sets.

Sevastova retired from tennis in 2013 after prolonged struggles with injury and illness, but returned two years later and now has the chance to crown a remarkable comeback with one of the game's major prizes.

After beating Stephens, the 19th seed was asked what her goals were upon returning to the game.

"Maybe top 100," Sevastova replied. "I was thinking, okay, maybe a couple of years, play top 100. Enjoy the game.

"But now, obviously when you win more, you have higher goals. And when you're, like, winning a tournament, you think that's normal. I can win it maybe next week again.

"But you have to appreciate it more, I think. You have to see that what you're doing, it's like a privilege, yeah. So I try to keep it [her expectations] low and try to enjoy it."

IT'S GETTING HOT IN HERE

For the second day in succession, oppressive heat made life exceedingly difficult for those playing in the day session, while junior matches were suspended between 1pm and 3:30pm.

Isner got through an extraordinary 11 shirts in his four-set defeat to Del Potro, his constant outfit changes earning appreciation from at least one source.

As Omnisport's reporter took his seat on Ashe ahead of the second set, a passing female spectator could be heard telling a passer-by: "We're happy. We saw Isner take his shirt off!"

"Is that the highlight of the tournament," the excited fan was asked.

"It is," came the reply. "We have very low expectations!"

DO I HAVE TO GO BACK OUT THERE?

Del Potro, meanwhile, joked that he was tempted to remain in the locker room after a 10-minute heat break was enforced, even though he led by two sets to one at the time!

In an on-court interview, the 2009 champion explained how he used up the brief period out of the sun's glare.

"I take a shower, then I re-taped my ankles, then I lay down on the table and then I didn't want to come back again," said the popular third seed.

"The heat - it's impossible to play tennis!"