Not even Mother Nature could stop a sensational, electrifying day of tennis on Monday.
Tommy Robredo earned the most shocking upset thus far, ousting five-time champion Roger Federer in five sets, while No. 83 Flavia Pennetta wasn't far behind with her stunning win over red-hot Simona Halep on the women's side.
Then you had David Ferrer beating Janko Tipsarevic in four physical sets, Rafael Nadal defeating Philipp Kohlschreiber in an extremely well-played match and Richard Gasquet outlasting Milos Raonic in a five-set thriller.
All-in-all, it was unquestionably the best day from Flushing Meadows so far.
Let's take a look.
Schedule of Play for Day 9's Top Courts
Day 9 Viewing Information
Where: USTA Billie Jean King National Tennis Center in Flushing Meadows, N.Y.
When: Tuesday, Sep. 3, starting at 11 a.m. ET
Watch: ESPN, ESPN2, Tennis Channel
Live Stream: WatchESPN
Predictions for Sunday's Top Stars
Serena Williams vs. Carla Suarez Navarro
These two have faced each other twice in their careers, with Williams taking both—one at the 2010 Australian Open, one at Rome earlier this year—easily in straight sets.
Navarro is coming off an impressive victory over Angelique Kerber in which she hit 45 winners, but no one catch touch Williams at her current level.
Not only has she dropped just 13 games in her first four matches, but she most recently took apart the very talented Sloane Stephens—who has the game to challenge her—in clinical, decisive fashion. She hit six aces and 22 winners to just 13 unforced errors, and she won 84 percent of her first serves.
As long as she continues to hold focus, Williams won't be slowed down in this one. She is simply playing on another planet right now.
Prediction: Williams wins, 6-3, 6-2
Novak Djokovic vs. Marcel Granollers
The only other time these two have played was in the first round of the Australian Open, where Djokovic rolled to a 6-1, 6-3, 6-1 win.
Now they're playing in the fourth round of the U.S. Open, highlighting just how easy the paths are for the top seeds in this tournament.
Marcel Granollers, who has made it this far at a major just once, has won each of his first three matches in an energy-sapping five sets, going the distance against Jurgen Zopp, Rajeev Ram and Tim Smyczek.
In two of those, he had to win the last two sets, and against Ram he had to win three in a row.
That shows incredible resolve, but you have to wonder what kind of toll—both mentally and physically—it is taking on him.
Of course, that doesn't really matter, because Djokovic, who has yet to drop a set, is far better than Granollers no matter how much the Spaniard might have left in his tank.
Granollers won't be backing down, but this one could be over in a hurry.
Prediction: Djokovic wins, 6-0, 6-3, 6-2