Sunday was a day of upsets right out of the gate during Round of 16 play on Arthur Ashe Stadium. Latvian Anastasija Sevastova continued her career-best Grand Slam run, defeating the 13-seed Johanna Konta; Caroline Wozniacki dropped World #9 Madison Keys; and Frenchman Lucas Pouille delivered the biggest win of his career, winning in a 5th-set tie-break over 2-time US Open Champion Rafael Nadal. Sunday night, it was business as usual – with both Angelique Kerber and Novak Djokovic advancing to the Quarterfinals in straight-sets…
Anastasija Sevastova (LAT) def  Johanna Konta (GBR)
Final 6-4, 7-5. Fearless. After retiring from the game in May of 2013, Anastasija Sevastova is back playing the best tennis of her career. She’s now upset World #3 Garbina Muguruza and World #14 Johanna Konta to reach her first career Grand Slam Quarterfinal…
First time for everything.
World No.48 Sevastova is through to 1st Major QF after ousting No.13 seed Konta 6-4 7-5 pic.twitter.com/IKZL7MPpoQ
— ESPNTennis (@ESPNTennis) September 4, 2016
Fun fact: Sevastova lost to Konta in the last Grand Slam match she played before retiring in 2013.
That was a QR1 match at the AO.
— Steven Mills (@StevenMtennis) September 4, 2016
Clever player, Sevastova. Puts ball in difficult places for opponents relying on metronomic power-hitting.
But a rough loss for Konta.
— DavidLaw (@DavidLawTennis) September 4, 2016
Caroline Wozniacki (DEN) def  Madison Keys (USA)
Final 6-3, 6-4. So…Caroline Wozniacki will be back in the top-50 after this year’s US Open. Back in the Quarterfinals for the 5th time, the 2-time US Open Finalist and former World #1 (for 67-weeks) had no problems dispatching the World #9 on Sunday.
Two-time finalist @CaroWozniacki cruises past Keys 6-3, 6-4!
— WTA (@WTA) September 4, 2016
GSM Caroline Wozniacki: “This is crazy. After such a tough year to be here and into the quarterfinals is amazing.” #USOpen
— WTA Insider (@WTA_insider) September 4, 2016
Caroline Wozniacki defeats No. 8-seed Madison Keys 63, 64 to advance to the QFs at a Slam for the first time since 2014 #USOpen.
— SI Tennis (@SI_Tennis) September 4, 2016
They just said Venus made her first finals at the us open in 97! I was 7 years old then.So impressive how she is still playing on this level
— Caroline Wozniacki (@CaroWozniacki) September 3, 2016
 Lucas Pouille (FRA) vs  Rafael Nadal (ESP)
Final 6-1, 2-6, 6-4, 3-6, 7-6(6). 2-time US Open Champion Rafael Nadal reached this year’s Round of 16 without dropping a set. In fact, he’d only lost 20-games en-route to the 4th-Round. Today, he lost 24…
After the first 10-minutes on court with Lucas Pouille, Nadal was down 0-3. 25-minutes later, he was a down a set. In the second, Rafa jumped ahead 3-0, then broke again to level the match (6-2). Set-3 saw Pouille draw first blood again, up a break before the first changeover. Lucas’ shot-making was superb, transitioning from defense to offense with ease, wrapping winners around the post, hammering forehands out of reach. He’d earn the third 6-4; but Rafa wasn’t done. He grabbed the upper-hand mid-way through the fourth and forced the decider…
How fitting was it that the 5th-set featured a tie-break? Pouille was actually down a break during the set, but climbed back – which is incredible considering the amount of tennis he’s played this week. Sunday’s 5th-set was his 19th-set of the 2016 US Open: He needed four to drop Kukushkin in Round-1, he saved match-point then won in five over Chiudinelli in Round-2, and he needed five to survive Bautista-Agut in Round-3. No question, the Frenchman’s fit…and he proved it Sunday evening.
Up 6-3 in the tie-break, with three match points on a 14-time Grand Slam Champion, he got the yips. Rafa erased all three match points, but Pouille kept on believing. Lucas held to earn match point #4, then delivered an unreachable winner to score the biggest win of his career, reaching his second consecutive Grand Slam Quarterfinal. He defeated Tomic in five to reach the Wimbledon Quarters, after dropping Juan Martin Del Potro in Round-3.
— US Open Tennis (@usopen) September 4, 2016
 Angelique Kerber (GER) def  Petra Kvitova (CZE)
Final 6-3, 7-5. Service-holds weren’t initially on the menu Sunday night. Kvitova was down a break at the first changeover, broke right back…then immediately fell behind again. She’d lose the set 6-3. Apparently the main course was reserved for set-2, where both held serve through the end. Kvitova’s serve was back. Kerber’s groundies were clinical. The south-paws put on a show from the baseline.
At 6-5 Kerber, Kvitova serving to stay in the match, the two threw-down some remarkable rallies. They battled to deuce, Kerber gained match point, and in an instant…Kvitova let it slip away. Serving to stay alive, Petra delivered let on her first serve. The next first-serve found the middle of the net. After a let on her second-serve, she send her fourth attempt long, handing the match to Kerber. Heart-break. Anticlimax.
— WTA (@WTA) September 5, 2016
 Novak Djokovic (SRB) def Kyle Edmund (GBR)
Final 6-2, 6-1, 6-4. Kyle Edmund had few answers for Novak Djokovic on Sunday night. Few do. While Novak had only played six games since his first round win Monday night (Vesely retired before their match in Round-2, Youzhny retired after six games on Friday), Edmund had become the darling of the fortnight, reaching his first Grand Slam Fourth-Round after upsetting Gasquet in Round-1 and John Isner in Round-3.
Kyle had taken a swing at Novak earlier in the year, at the Masters-1000 event in Miami, where he managed six games off the World #1. Tonight, he’d win 7. Next up for Novak: Jo-Wilfreid Tsonga. Djokovic and Tsonga have played 21-times. Novak’s won 15 of their previous matches, including their most-recent clash earlier this year at Indian Wells, where Djokovic won in two tie-break sets.
— BBC Tennis (@bbctennis) September 5, 2016
DAY-7 UPSETS AND INTRIGUING RESULTS
-  Jo-Wilfried Tsonga (FRA) def  Jack Sock (USA) 6-3, 6-3, 6-7(7), 6-2. Jack carried a ton of confidence into his 3rd-Round match with World #9 Marin Cilic. After all, he’d been there, done that. Back in July, he came from 2-sets down to defeat Marin in the Davis Cup Quarterfinals in Portland – one of the biggest wins of his career. He used that experience to punt the 2014 US Open Champ in straight-sets. Sunday was his first time across the net from Jo-Wilfried Tsonga. Jack had no frame of reference. It was uncharted teerritory. Tsonga took full advantage. The World #11 was up 2-sets within an hour. Jack kept the match alive with a huge tie-break win in the third, but he couldn’t stem the bleeding. Tsonga advanced to his third US Open Quarterfinal and 22nd career match-up with Novak Djokovic.
-  Bob Bryan / Mike Bryan (USA) def David Marrero / Fernando Verdasco (ESP) 2-6, 6-3, 7-5. TOUGH Round-3 match-up for Bob and Mike. David and Fernando won the doubles title at the ATP World Tour Finals in 2013. After the first set, it was looking like Bob and Mike would be sent packing early…but the brothers – as they’ve done a million times – found a way, and climbed to the US Open Quarterfinals for the 11th-time. The Bryans are on the hunt for their 6th US Open title.
- Asia Muhammed / Taylor Townsend (USA) def  Timea Babos (HUN) / Yaroslava Shvedova (KAZ) 0-6, 6-4, 6-3. Huge win of the Americans after suffering a first-set bageling. The young Americans are through to the Quarterfinals where they’ll meet Bethanie Mattek-Sands and Lucie Safarova.
- Nicole Gibbs / Denis Novikov (USA) def  Hao-Ching Chan (TPE) / Max Mirnyi (BLR) 7-5, 7-6(2). Mixed Doubles Upset! Reminiscent of Jack Sock and Melanie Oudin’s run to the Mixed Doubles title 5-years-ago – let’s hope Nicole and Denis can keep it going here in Flushing.
- Barbora Krejcikova (CZE) / Marin Draganja (CRO) def  Sania Mirza (IND) / Ivan Dodig (CRO) 6-3, 6-4. Clearly, the biggest Mixed Doubles upset of the day.