US Open Tennis 2016 Results: Scores, Highlights from Early Monday Results

Serena Williams and Andy Murray headlined a star-studded Labor Day at the 2016 U.S. Open as the fourth round of the season's final major came to a close Monday.

While the tournament has witnessed some notable upsets, including the exits of Rafael Nadal and Garbine Muguruza, most of tennis' marquee names were still in the mix to start the second week. It should make for a memorable finish to the Grand Slam finale. 

Let's check out the matches and scores from Monday's holiday slate. That's followed by a recap of the day's top storylines.

Monday's Match Results

Round	Matchup/Result	Score
	Men's Tournament
Fourth	(2) Andy Murray d. (22) Grigor Dimitrov	6-1, 6-2, 6-2
Fourth	(3) Stan Wawrinka d. Illya Marchenko	6-4, 6-1, 6-7, 6-3
Fourth	(6) Kei Nishikori d. (21) Ivo Karlovic	6-3, 6-4, 7-6
Fourth	Juan Martin del Potro d. (8) Dominic Thiem	6-3, 3-2, ret.
	Women's Tournament
Fourth	(1) Serena Williams d. Yaroslava Shvedova	6-2, 6-3
Fourth	Ana Konjuh d. (4) Agnieszka Radwanska	6-4, 6-4
Fourth	(5) Simona Halep d. (11) Carla Suarez Navarro	6-2, 7-5
Fourth	(10) Karolina Pliskova d. (6) Venus Williams	4-6, 6-4, 7-6

Day 8 Recap

Simona Halep has flown below the radar for most of the tournament, but the No. 5 seed has now reached the quarterfinals while dropping just a single set as she seeks her first major title. Her latest win came in mostly routine fashion against the always game Carla Suarez Navarro.

The 24-year-old Romanian, who reached the semifinals in New York last year, rebounded from a mundane effort against Timea Babos with a highly efficient showing Monday. She finished the 6-2, 7-5 victory with 25 winners and four aces compared to 18 unforced errors and no double-faults.

U.S. Open Tennis passed along a highlight from the final game that encapsulated most of the match. Suarez Navarro simply didn't have the necessary weapons to keep pace:

Questions remain about Halep's ability to overcome the top power players on the big stage. She'll get another look at the best of them all, Williams, as the top seed is her quarterfinal opponent. Her record against the game's gold standard is just 1-7.

Hopes of a Williams sisters semifinal ended Monday afternoon as Karolína Pliskova fought back after dropping the first set against Venus Williams to get the biggest Grand Slam win of her career.

There were just too many mistakes over the final two sets for Williams, who finished the match with 40 unforced errors. It allowed the 24-year-old Czech underdog, who faced a match point late in the third set, to earn the memorable win.

ESPN Stats and Info provided further information about the end of a drought:

Pliskova has the power to keep the magical run going, as illustrated by her 119 winners and 29 aces through four rounds. Now the question is how she'll handle the pressure of making the deepest Grand Slam run of her career.

Two days after getting pushed to the limit by Daniel Evans, Stan Wawrinka once again found himself in a hard-fought battle with an unseeded player. This time it was Illya Marchenko who took a set off the two-time Grand Slam champion.

The Swiss star, who's made the semifinals in New York two of the past three years, almost found himself in even more trouble if not for some clutch play on his serve. In turn, Marchenko converted just three of 10 break-point opportunities.

Wawrinka will need to elevate his form in order to make a serious push toward the title, though. His next opponent, reigning Olympic silver medalist Juan Martin del Potro, certainly isn't taking him lightly despite the last few matches, as Christopher Clarey of the New York Times pointed out:

That match should be fun to watch, regardless of which player comes out on top. Between Del Potro's forehand power and Wawrinka's wicked backhand, there will be no shortage of highlight-reel rallies as they trade jabs, likely for four or five sets.

At this point it's hard to believe Serena Williams came into the tournament with question marks about her ability to make a deep run. She lost in the third round of the Olympics while dealing with a shoulder injury, but she's looked no worse for wear so far in the U.S. Open.

She made quick work of Yaroslava Shvedova to complete a run to the quarterfinals during which she didn't lose more than three games in any set. The latest win featured 28 winners and 11 aces to go along with only 13 unforced errors.

The victory also allowed her to add another record to her already amazing resume, per SportsCenter:

Ultimately, Williams heads into the quarters in a position she's assumed countless times: the overwhelming favorite. It's going to take either an off day from her or a special one from somebody else to prevent her from capturing her 23rd major singles title.

Like Williams on the women's side, Murray made quick work of his opponent on the men's. 

He handled Grigor Dimitrov in straight sets, 6-1, 6-2, 6-2. The Olympic gold medalist looks like the biggest threat to No. 1 Novak Djokovic for the remainder of the tournament, especially since Nadal already lost. 

Not all of the highly seeded players won on Monday, as Ana Konjuh upset No. 4 Agnieszka Radwanska in the women's bracket. Konjuh didn't just win, she pulled off the upset in straight sets, 6-4, 6-4. Konjuh controlled things with her serve and notched six aces to only two for Radwanska. She also won an overwhelming 86 percent of her first-service points.

All match statistics courtesy of the tournament's official site.