What impressions are we left with about the U.S. Open as a whole? Let's consider the women's and men's tournaments separately.
I have in the past called the women's game, "Serena, and a parade of also-rans." Based on the results here, it appears, though, that this is starting to change. Here at the Open, when top players lost, they tended to lose to very strong players. Halep lost to Sharapova. Sharapova lost to Sevastova, who lost to Stephens. (I think we can now put Stephens into the the conversation as a top player.) Kvitova beat Muguruza. Venus beat Kvitova, and Stephens beat Venus. Last year's finalist, Karolina Pliskova, made it to the quarters before losing to Vandeweghe. Vandeweghe lost to Keys in the semis. Svitolina and Vesnina also lost to Keys. So there is some sense that we're beginning to see a consistent field of top players atop the women's game.
The men's game, on the other hand, is in a bit of a tough spot right now. With Djokovic, Murray, Wawrinka, Nishikori and Raonic all out with long-term injury, the Open lost a lot of its shine. And many of the players who did play hardly wowed us. Sascha Zverev, considered by many the top young player, lost in the second round. Thiem succumbed to the arduousness of his own style of play as much as Del Potro's play on the other side of the net. Monfils made the third round before retiring against Goffin. Goffin made the round of sixteen, but only because he stubbornly refused to retire did his round-of-sixteen match go three whole sets--and the player who beat him, Andrey Rublev, got crushed in the next round by Nadal. None of Berdych, Dimitrov, Kyrgios and Gasquet made it out of the second round.
Even players with more positive results struggled. Federer made the quarters, despite mostly lackluster play. Del Potro made the semis and took a set off Nadal before he ran out of gas. And Anderson made his first final, where he was totally overwhelmed by Nadal.
Aside from Nadal's play, about which more in a moment, the best thing about the Open might have been that young Denis Shapovalov made the round of 16 on the back of his fun, stylish play. I very much look forward to seeing more of him.
So, Nadal: he was a clear level, maybe two, above everyone else in the field. Yes, he dropped first sets in three of his seven matches, but once the match got rolling, so did Nadal. He didn't once face a fifth set. It may not have been quite as dominating a victory as what he accomplished at Roland Garros a few months ago, but nonetheless, he was never under any serious pressure. A couple of years back, I said that he would never again regain top form, that his style of play had taken too much out of him over the years. I was wrong.