Australian Open 2015: Twitter Reacts to Day 4 Bracket Results, Scores, Winners

There were no significant upsets on Day 4 of the 2015 Australian Open. Instead, it was a day where many of the tournament's top contenders in both draws shined. The group was lead by the top seeds, Novak Djokovic and Serena Williams.

The first three days of the event were littered with upsets. While there were some minor ones on Thursday, it seemed like those previous notable results provided a wake-up call. A fresh reminder that the margin for error on the sport's biggest stages is small.

With that in mind, let's check out the results from both brackets along with analysis and social-media reaction for some of the most noteworthy matches. For a look at the schedule coming up on Day 5, visit the tournament's official site.

Day 4 Men's Results and Reaction

Round	Winner	Loser	Score
Second	(1) Novak Djokovic	Andrey Kuznetsov	6-0, 6-1, 6-4
Second	(4) Stan Wawrinka	Marius Copil	7-6, 7-6, 6-3
Second	(5) Kei Nishikori	Ivan Dodig	4-6, 7-5, 6-2, 7-6
Second	(8) Milos Raonic	Donald Young	6-4, 7-6, 6-3
Second	(9) David Ferrer	Sergiy Stakhovsky	5-7, 6-3, 6-4, 6-2
Second	(12) Feliciano Lopez	Adrian Mannarino	4-6, 4-6, 7-6, 4-0 ret.
Second	Gilles Muller	(13) Roberto Bautista Agut	7-6, 1-6, 7-5, 6-1
Second	Jerzy Janowicz	(17) Gael Monfils	6-4, 1-6, 6-7, 6-3, 6-3
Second	(18) Gilles Simon	Marcel Granollers	7-6, 6-2, 6-4
Second	(19) John Isner	Andreas Haider-Maurer	6-4, 7-6, 4-6, 6-4
Second	Steve Johnson	(30) Santiago Giraldo	6-3, 6-4, 6-2
Second	(31) Fernando Verdasco	Go Soeda	6-3, 6-2, 7-6
Second	Benjamin Becker	Lleyton Hewitt	2-6, 1-6, 6-3, 6-4, 6-2
Second	Jarkko Nieminen	Matthias Bachinger	7-6, 7-5, 7-5
Second	Vasek Pospisil	Paolo Lorenzi	6-7, 7-6, 6-3, 6-4
Second	Guillermo Garcia-Lopez	Alejandro Gonzalez	6-1, 6-3, 6-3

There was some concern about Djokovic coming into the tournament. His practice scheduled was cut short due to an illness, which raised questions about his readiness. Those concerns are now firmly in the rear-view mirror after a pair of victories in straight sets.

The latest one being an absolutely dominant showing against Andrey Kuznetsov. It wasn't until the middle of the second set that the underdog finally won a game. Afterward, the Serbian sensation talked about his comfort level at Melbourne Park, as the tournament feed noted:

Reigning champion Stan Wawrinka was seriously tested by heavy-hitting Marius Copil for the first two sets. Luckily for the No. 4 seed, he was able to show his championship mettle in the tiebreaks. Otherwise the story might be a lot different.

Not only was he playing with fire for a couple sets, but he also played some lackadaisical games along the way. Howard Bryant of ESPN pointed out this isn't the point of a tournament where players want to risk any extra time spent on the court:

It was a frustrating day for Donald Young. The enigmatic American still flashes high-end form from time to time, but those moments are fleeting. He was no match for powerful Canadian Milos Raonic, who advanced in straight sets.

Young will have to bring more consistency to his game if he's going to become a threat on the Grand Slam stage. That said, it's important to give some credit to the No. 8 seed and possible title contender, who played a great match, according to Brad Gilbert of ESPN:

The most entertaining match of the day featured Jerzy Janowicz and Gael Monfils. It's no shock the French showman was involved. His matches always have some added flair. But the minor upset could be a key turning point for Janowicz.

He was a breakout star at Wimbledon in 2013, but has since struggled to reach expectations. Beating Monfils is a step back in the right direction. Nick McCarvel of USA Today considers the question many tennis fans are thinking about after the win:

John Isner and Steve Johnson both advanced to give the top half of the bracket some American presence. Johnson was particularly impressive as he cruised past 30th-seeded Santiago Giraldo in straights. It sets up a meeting with Kei Nishikori in the third round.

It was a disappointing day for home fans at the season's first major. Fan favorite Lleyton Hewitt rushed out to a two-set lead over Benjamin Becker before the German veteran stormed back to win in five. Once the momentum changed changes, Hewitt could never get it back.

Fernando Verdasco picked up a convincing victory over Go Soeda to reach Round 3. His form tends to rise and fall without much warning. But if he can put together one of his better performances, he should provide Djokovic with his first big test of the tournament next time out.

Day 5 should be a good one on the men's side. Roger Federer, Rafael Nadal and Andy Murray are all in action. There's also a heavy Australian group still left standing on the bottom half of the draw, which should bring the crowds alive around the grounds.

Day 4 Women's Results and Reaction

Round	Winner	Loser	Score
Second	(1) Serena Williams	Vera Zvonareva	7-5, 6-0
Second	(4) Petra Kvitova	Mona Barthel	6-2, 6-4
Second	(6) Agnieszka Radwanska	Johanna Larsson	6-0, 6-1
Second	Victoria Azarenka	(8) Caroline Wozniacki	6-4, 6-2
Second	(11) Dominika Cibulkova	Tsvetana Pironkova	6-2, 6-0
Second	(18) Venus Williams	Lauren Davis	6-2, 6-3
Second	(19) Alize Cornet	Denisa Allertova	6-4, 6-7, 6-2
Second	Coco Vandeweghe	(20) Samantha Stosur	6-4, 6-4
Second	(24) Garbine Muguruza	Daniela Hantuchova	6-1, 1-6, 6-0
Second	(25) Barbora Zahlavova Strycova	Kai-Chen Chang	6-1, 7-5
Second	(26) Elina Svitolina	Nicole Gibbs	7-6, 7-6
Second	Madison Keys	(29) Casey Dellacqua	2-6, 6-1, 6-1
Second	(30) Varvara Lepchenko	Ajla Tomljanovic	6-1, 7-6
Second	Timea Bacsinszky	Anna Tatishvili	6-7, 6-3, 6-2
Second	Madison Brengle	Irina Falconi	6-1, 6-3
Second	Camila Giorgi	Tereza Smitkova	6-1, 6-4

Williams should why she's the player to beat every time she steps on the court in a major. She fell behind Vera Zvonareva, who represented a tricky test in Round 2, by a 5-3 score in the opening set. Her response to that pressure was incredible.

The 18-time Grand Slam singles title winner won the next 10 games to turn that deficit into what looks like a simple triumph on the scoresheet. Jon Wertheim of Sports Illustrated pointed out the match followed a similar script to a meeting more than a decade ago:

The marquee matchup of the day on the women's side seen Victoria Azarenka edge Caroline Wozniacki. The former world No. 1 entered the tournament unseeded after overcoming some injury woes. The match served as a sign she's getting back toward full strength.

Unfortunately for Wozniacki, the story remains much the same. She's a very good player but against the select group of top power players, she comes up a bit short. But the biggest story coming out of this match is the one mentioned by Ben Rothenberg of the New York Times:

Petra Kvitova is yet another dangerous player in this section of the draw. She's had some recent struggles in this event, getting knocked out before the third round each of the last two years. She was able to avoid the same fate this time by easing past Mona Barthel.

Kvitova has won Wimbledon twice, including last year. Now she's looking to expand her trophy case to one of the other majors. Christopher Clarey of the New York Times notes she'll face a much tougher test in Round 3:

Venus Williams is also moving onto the third round as her resurgence continues. After some down years by her incredibly high standards, she looks ready to make a serious impact in 2015. That was evident as she made quick work of fellow American Lauren Davis on Thursday.

She's in a tricky part of the draw with Kvitova and Agnieszka Radwanska, but if things fall her way she could meet sister Serena in the semifinals. While that would be a must-see event, for now she just seems happy to be playing well, as evidenced by a joke passed along by the Open:

Coco Vandeweghe and Madison Keys are also part of the improving results for United States' women's tennis. They both moved on, as well. Each of them scored a winner over a seed Australian, Samantha Stosur and Casey Dellacqua, respectively.

Varvara Lepchenko and Madison Brengle also followed suit. That gives the U.S. six of the 16 players remaining in the top half of the women's draw. Although it's still very early, that paints a positive picture for the rest of 2015.

Looking ahead to Day 5, Maria Sharapova returns to the court after receiving a scare from Alexandra Panova to face Zarina Diyas. Simona Halep, Eugenie Bouchard and Ekaterina Makarova are also in action as the tournament begins to heat up.