Matthew Stockman/Getty Images
By Courtney Nguyen
September 01, 2014

NEW YORK -- Week One of the U.S. Open has come and gone, with the headlines dominated by a flurry of upsets on the women's side, youngsters like CiCi Bellis, Belinda Bencic, and Dominic Thiem making a big splash in their New York debuts, and the heart-warming return of Mirjana Lucic-Baroni to the business end of a major. As we transition to the second week, here are the storylines to watch:

Serena Williams aims to cap off her Slam season by doing the double: This is a failure of a season if Serena doesn't win the U.S. Open. Even though she's admitted as much, she's also been trying to diffuse as much pressure as possible as she goes for Slam No. 18. Through four matches she hasn't come close to losing a set. Her serve continues to be monstrous and her footwork and focus has been solid. She's playing well enough to win this title and she's still in doubles with Venus. Winning the singles and doubles would be pretty sweet after the year Serena has had. 

Novak Djokovic and Andy Murray clash in the quarterfinals: The two have played each other five times at the Slams but never as early as the quarterfinals. After beating Jo-Wilfried Tsonga in straight sets to earn his first top 10 win since winning Wimbledon last year, Murray, seeded eighth, will go for his first top five win over the same span. As for Djokovic, he has not lost a set through four matches. He's the obvious favorite going into the match -- he leads the head-to-head 12-8 -- but if Murray really is back to playing some of his best tennis, this will be a great benchmarking match for the Brit. 

Caroline Wozniacki beats Maria Sharapova to make U.S. Open quarterfinals

Caroline Wozniacki looking to make her first Slam final in five years: The stars seem aligned for Wozniacki to cap off her great summer form to make the U.S. Open final for the second time, having done so in 2009 when she lost to Kim Clijsters. This is the first time since that 2009 Open that only one of the top eight seeds has made the quarterfinals -- once again, it's Serena -- and Wozniacki's half of the draw has been decimated by upsets, including her own win over fifth-seed Maria Sharapova. She plays Sara Errani in the quarterfinals and then either Peng Shuai or Belinda Bencic. She has a winning record against all three, including a 6-0, 6-0 win over Bencic in Istanbul in July. 

Can anyone stop Roger Federer from making another tournament final? Grigor Dimitrov? Gael Monfils? Tomas Berdych? Those are the only men you can bank on giving Federer a test before the final. Federer has lost just one set -- an odd rain-interrupted one to Marcel Granollers -- en route to the fourth round. He plays 17th-seed Roberto Bautista Agut for the first time in the fourth round. The impressive aspect of Federer's game through the first week has been his movement. He's covering the court incredibly well.

Belinda Bencic walking in Martina Hingis' footsteps: It was after midnight on Monday morning when a journalist asked a beaming Belinda Bencic a question about being the youngest woman to make the quarterfinals of the U.S. Open since her mentor Martina Hingis in 1997. Bencic's face twisted. It didn't seem she understood the question at first. But that confusion wasn't about language. She just couldn't believe it. "Really?!?" she asked with an air of incredulity. Yeah, we can't believe the coincidence either, Belinda. But the 17-year-old beat two top 10 players to earn her spot in the quarters and she has a chance to go even further when she faces Peng Shuai. Oh, and by the way, that year Hingis made the U.S. Open quarterfinals as a 16-year-old? Yeah, she ended up winning the tournament. 

While we're at it, let's temporarily rename it The Swiss Open: Roger Federer, Stan Wawrinka, and Belinda Bencic are all into the second week of a major. Their plans for global domination begins. 

Bob and Mike Bryan go for 100: The twins captured their 99th career title at the Western & Southern Open. New York would be a great place to snag No. 100. 

CiCi Bellis goes for the junior title: The 15-year-old who grabbed headlines in the senior tournament last week is now back to earth and playing the junior tournament as the No. 1 seed. Well, not completely back to earth. How many juniors do you know who have had their first round match scheduled for Grandstand?

Entertainers battle head-to-head: Grigor Dimitrov and Gael Monfils, the two men who dominate the ATP's Hot Shot reels, will face off at Arthur Ashe Stadium on Tuesday. Here's what you can count on: Dimitrov will find himself on the ground more than once, Monfils will hit a shot you've never seen before (that may not actually land in), and it's going to be one of the most entertaining matches of these two weeks. Oh, and there might a little awkwardness at the net: