NEW YORK – The joint is still jumping after an epic quarterfinal match last night between defending champion Rafael Nadal and his natural successor, Dominic Thiem.
But there are four more men’s and women’s quarterfinals on tap Wednesday.
The heat rules are in effect again – and likely will be again on Thursday. But after that, for the meaty end of the tournament, the temperatures will cool down considerably even if the humidity looks as though it will be a stubborn opponent to defeat.
So it’s another day of survival.
And we’ll see if 29-year-old upset artist John Millman, who eliminated Roger Federer Monday night, has enough left to double his pleasure against Novak Djokovic in another night match.
 Marin Cilic (CRO) vs.  Kei Nishikori (JPN)
These two met in the 2014 US Open final, as Cilic won his first (and so far, only) Grand Slam title, and Nishikori reached his first (and so far, only) Grand Slam final.
This is Nishikori’s 14th major since then, and only once has he gone past the fourth round. Two years ago, he reached the semifinals in New York. And in between, he dealt with a wrist issue that crushed the second half of his 2017 season, and which he is only just now starting to truly shake off to find his best form.
Cilic was a Wimbledon finalist last year, when blisters scuttled his effort against Roger Federer. He reached another final to start this season in Australia, benefiting from a late-match withdrawal from Rafael Nadal in the quarterfinals. He gave a much better account of himself against Federer in the final, losing in five sets.
Is this his year? He has already survived a late-night thriller against 19-year-old Aussie Alex de Minaur. That match was by far the best of the tournament – until Nadal and Dominic Thiem lit up Arthur Ashe Tuesday night.
This matchup is actually a pretty great, low-key rivalry, with Nishikori leading it 8-6. This is their fourth meeting at the US Open, going back to a five-setter in 2010 tha was played in brutal conditions similar to the ones we’ve experienced this year.
Nishikori, who had come through the qualifying, emptied the tank on that one and retired early in the second set of his next match, against Albert Montañes of Spain.
 Naomi Osaka (JPN) vs. Lesia Tsurenko (UKR)
Osaka likely survived a hard-hitting battle against fellow 20-year-old Aryna Sabalenka far better than Tsurenko, unseeded, did against Marketa Vondrousova of the Czech Republic in the fourth round.
Tsurenko was dizzy, overcome with the heat at times. And although she survived, she likely doesn’t have much left after a great run to the quarterfinals.
Osaka’s win was an emotional one Monday. She was outplayed at times in an error-filled battle. But she hung in there and in the end, good things came.
The winner of this one plays the winner of a match between Madison Keys and newly-30 Carla Suarez Navarro, for the right to play in the US Open final.
The stakes are huge. And the task is doable.
 Madison Keys (USA) vs.  Carla Suárez Navarro (ESP)
When your seeding matches your age, perhaps it’s your time.
Suárez Navarro has flinched in big moments in her career, her self-belief never quite at the level of her entertaining game.
But in defeating former top-10 Kristina Mladenovic, current top-10 Caroline Garcia and five-time Slam champion Maria Sharapova in back-to-back-to-back matches, perhaps that time has finally come.
In Keys, she faces a player who has everything it takes, talent-wise and physically, to win a Grand Slam. Multiple Grand Slams, in fact.
But at 23, she hasn’t yet quite put it together. Even if she has two major semifinals and last year’s US Open final against her BFF Sloane Stephens on her resumé already.
The optimal formula hasn’t yet settled in – a consistent team and coaching voice that can build a rapport and elevate her game to where it can be.
Keys has time on her side. And, she has a 3-0 record against Suárez Navarro, whom she hasn’t played since the 2016 Olympics in Rio. All three have gone the distance, though. And Keys had to come back from a set down to win two of them.
The winner plays Osaka or Tsurenko for a shot at the final. In the decimated women’s draw, this is called a huge opportunity.