It’s only been five days, and already, we’re guaranteed of having a first-time Grand Slam men’s finalist.

Diego Schwartzman’s four-set victory over 2014 US Open winner and No. 5 seed Marin Cilic registered another seismic blow to a half of the draw utterly decimated by upsets. And to add further tumult to the disorder, No. 10 seed John Isner followed Cilic out the turnstiles, dismissed by No. 23 Mischa Zverev.

The result: World No. 19 Pablo Carreno Busta is the highest-ranked player remaining in the bottom half of the men’s draw; only Friday winner Sam Querrey has ever made a Grand Slam semifinal – and he has made only one, at Wimbledon just two months ago; and in total, the eight men remaining have reached a grand total of seven Grand Slam quarterfinals – two by Querrey (2016-17 Wimbledon) and Lucas Pouille (2016 Wimbledon, 2016 US Open) and one each by Zverev (2017 Australian Open), Carreno Busta (2017 French Open) and Kevin Anderson (2015 US Open).

For comparison, Roger Federer has reached 50 Grand Slam quarterfinals in his career, including 36 in a row from 2003 to 2013.

The women’s draw, on the other hand, progressed with surprising continuity. In a tournament rife with upsets, seeds Garbiñe Muguruza, Venus Williams, Anastasija Sevastova and Julia Goerges all advanced with ease, and all eight Day 6 winners but Carla Suarez Navarro won in straight sets.

Here’s a look back at Day 5 of the 2017 US Open – heretofore forever known as the birthday of Serena Williams’ daughter – and a look ahead to Day 6:

Match of the Day

2014 US Open champion Marin Cilic was the lone remaining giant in the bottom half of the men’s draw. On Friday in the Grandstand, he was brought down by 5-foot-7 Diego Schwartzman, the shortest man in the bracket, in a riveting four-setter, 4-6, 7-5, 7-5, 6-4.

Schwartzman has flown under the radar (pun intended) for much of the year, quietly ascending into seeded territory behind a return game that ranks as the best in the sport (breaking on 35 percent of his opponent’s service games, better than even perennial top dogs Rafael Nadal and Novak Djokovic). On Friday, he generated 20 break-point chances against the booming delivery of the 6-foot-6 Cilic, converting an impressive nine of those opportunities.

And in the end, when Cilic cut a two-break, fourth-set lead down to one, earning break points at 5-4, Schwartzman came up big (yes, pun intended again), fighting off the break points and grinding out the victory. With that, the pint-sized Argentine is into the fourth round of a Grand Slam for the first time, eclipsing his round-of-32 showing at Roland Garros earlier this year. And coming on the heels of a run to the quarterfinals of the Masters 1000 event in Montreal prior to the US Open, he is building the momentum that could very well carry him deep into what is now a wide open draw. 

Player of the Day

Garbiñe Muguruza won the French Open in 2016 and Wimbledon this summer. She has advanced to the quarterfinals at the Australian Open, climbed to No. 2 in the world and currently checks in at No. 3. Yet for all her success around the globe, the 23-year-old Spaniard had always sputtered in New York, entering this year’s event with a 2-4 career record in Flushing and having never advanced past the second round.

On Friday, she eclipsed her career US Open win total by claiming her third consecutive victory to advance to the fourth round. And she is not just winning matches; she is annihilating her opponents, transforming herself in one short week from US Open underachiever to US Open favorite.

Her latest victim was Wimbledon semifinalist Magdalena Rybarikova, who on Friday managed just two games in a 6-1, 6-1 loss. In all, Muguruza has surrendered just nine games in six sets and has spent a meager three hours and nine minutes on court – or 22 minutes less than Shelby Rogers did Thursday alone in her victory over Daria Gavrilova. Three of her sets have taken less than half an hour, with the longest checking in at 44 minutes.

The short matches should serve Muguruza’s title ambitions well in that she should be rested for the stretch run – a difficult section of the draw that features No. 13 Petra Kvitova in the next round, with a potential blockbuster quarterfinal against No. 9 Venus Williams awaiting in Week 2.

Upset of the Day

The US Open’s third round has bedeviled John Isner throughout his career. Entering the 2017 edition of America’s Grand Slam, the skyscraping American had played in 10 US Opens. Six times he had lost in the round of 32, including in four of the last five.

Friday evening in Arthur Ashe Stadium, history repeated itself. The No. 10 seed – the highest remaining seed in the bottom half of the men’s draw when he took the court – was eliminated in the third round once again, this time by hard-charging No. 23 seed Mischa Zverev, the 2017 Australian Open quarterfinalist who is enjoying a surprise breakout season at age 30.

Zverev’s 6-4, 6-3, 7-6 victory was more a testament to his own shot-making and clean play – the serve-and-volleyer (yes, they still exist) committed just seven unforced errors in the match – than to the shortcomings of Isner. But the loss will sting nonetheless. The numbers tell the tale: 11 trips to New York, seven third-round exits and one disappointed American who will surely rue a golden missed opportunity. 

play video Cognitive Highlight: Mischa Zverev - Round 3

Quote of Day

“I hope maybe they can understand tennis is for everyone. Is not just for the tall guys. Sometimes it's helping a lot if you are big, because you can serve fast, you can do everything fast on the baseline because you have more – the arms are bigger than me. But … I was always like this, and I always try to improve my tennis and try [not] to think about [it].” – Diego Schwartzman, 5-foot-7, after upsetting 6-6 Marin Cilic to reach the fourth round

Day 6 Preview

The unmarred half of the men’s draw is back on the court Saturday, with Roger Federer and Rafael Nadal looking to continue their march toward a highly anticipated semifinal. Nadal will go first, wrapping up the day session in Arthur Ashe Stadium against Leonardo Mayer, with Federer leading off the evening against Feliciano Lopez – the second consecutive 35-year-old opponent for the 36-year-old Swiss.

A quartet of Americans will be in action as the women wrap up their third round, headlined by No. 15 Madison Keys against No. 17 Elena Vesnina and No. 20 CoCo Vandeweghe taking on No. 10 Agnieszka Radwanska. Also set to kick off the weekend are No. 1 Karolina Pliskova, against No. 27 seed Zhang Shuai, and 2017 French Open champion Jelena Ostapenko, who takes on Daria Kasatkina in a matchup of rising stars.