US Open Tennis Schedule 2013: Day 12 Matchups, Predictions and Analysis

The top female players in the world are in action Friday at the U.S. Open as they compete in the tournament semifinals.

After eventful quarterfinals on both sides of the draw, Serena Williams and Victoria Azarenka will try to avoid upsets as the No. 1 and No. 2 players in the world. If these stars advance, the final will be the same as last year—when Williams came away with the win.

Of course, Williams could have a busy day, as she will play with her sister, Venus Williams, in the doubles semifinal as well. The pair will face Andrea Hlavackova and Lucie Hradecka in a rematch of last year's Wimbledon final.

The entire day is certain to be entertaining, so take a look at this guide to Day 12 at the U.S. Open.

Note: For the complete Schedule of Play for Day 12, click here. For a complete look at the updated draws, click here. Links courtesy of USOpen.org.

Top Matchups 

Flavia Pennetta vs. No. 2 Victoria Azarenka

Throughout her career, Flavia Pennetta has loved playing at the U.S. Open. She has reached the quarterfinals three times and is set to play in her first career semifinal.

Amazingly, she has never advanced beyond the fourth round in any other Grand Slam.

Still, the Italian has been incredible so far in the tournament. Live Tennis provided this interesting statistic about the unseeded player:

This is certainly impressive, especially considering she has a win over Sarah Errani, but there is still a big jump in talent when it comes to Victoria Azarenka.

The No. 2 player in the world is a two-time Australian Open winner, and she reached the final of last year's U.S. Open. When it comes to hard courts, Azarenka is as good as they come.

At this point, the question is whether the talented player will beat herself. In each of the two sets she lost in this tournament, she really only had herself to blame. She had five double faults and 20 unforced errors against Alize Cornet, and she had only four winners in a set against Ana Ivanovic.

It will be important to avoid a poor showing like that against Pennetta—or at least limit the damage to one set. With the tournament on the line, she should be able to at least accomplish that latter feat in a win.

Prediction: Azarenka wins 6-4, 3-6, 6-3

No. 1 Serena Williams vs. No. 5 Li Na

Li Na has quietly had an impressive year, climbing to No. 6 in the world rankings. This is her second Grand Slam semifinal of the season, as she reached the finals of the Australian Open. She also reached the quarterfinals of Wimbledon before falling to Agnieszka Radwanska. 

Her best attribute is her ability to return serves at an incredible rate, especially against second serves. Unfortunately, this will not be easy against the strong serve of Serena Williams.

Williams has simply overpowered opponents in this tournament, winning every set and hardly breaking a sweat. In her latest match, she embarrassed Carla Suarez Navarro with a double bagel, as noted by ESPN Stats and Information:

The No. 1 player in the world regularly tops 100 mph with her serve and can maintain it even after missing with her first shot. She can also vary the direction, causing many problems for opponents hoping for a return.

As good as Li usually is defensively, her strength is does not match up well with her opponent's strength. That's why Williams has won eight of nine career battles between the two.

Friday will extend Williams' success, and the top seed will move on to the finals.

Prediction: Williams wins 6-2, 6-2

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