US Open Tennis 2013 Women's Finals: Keys for Serena Williams, Victoria Azarenka

For the second straight year, Serena Williams and Victoria Azarenka will square off for the U.S. Open women's championship inside Arthur Ashe Stadium in Flushing, N.Y.

Williams won her fourth career U.S. Open crown in 2012 after defeating Azarenka in a memorable three-setter. She didn't drop a set en route to the final last year and is on the same blistering pace in 2013, having lost just 16 games total over the past two weeks.

But despite all of her success to this point, Williams still has to get through the world No. 2, who has won two of their three meetings in 2013. 

Below we'll examine the biggest keys for each contender in Sunday's match.

Keys for Serena Williams

Keep Mixing It Up on Serve

Williams hasn't recorded more than six aces in a match through the first six rounds, but has been dominant on serve throughout, putting a high percentage of first balls into the box and winning an even higher percentage of those points.

The best server women's tennis has ever seen, Serena has a variety of serves at her disposal and is tremendously successful with each. 

Whether she's going out wide, down the line, or into Azarenka's body, Williams' unrivaled pace is sure to trouble her opponent and be a huge factor throughout.

Limit the Errors

Another key for Williams on Sunday will be her ability to limit unforced errors. To this point in the tournament she has been exceptional in this category, committing only 13 per match on average.

Williams has had more winners than errors in all but one match en route to the final, but it's not about striking winners against Azarenka. If the 16-time Grand Slam champion can remain patient and force her opponent to chase winners, she's likely to succeed.

Azarenka has struggled to keep her unforced error count down throughout the tournament, and has committed 30 or more in her two three-set matches in Queens. TennisViewMag.com's Chris Skelton provides a comparison between the two players through six rounds:

The world No. 2 will have her moments of brilliance and her fair share of winners, but if Williams can play smart, patient tennis, she'll be at a mighty advantage given her ability to dominate on serve.  

Keys for Victoria Azarenka

Find Success on the Second Serve

For Victoria Azarenka, finding success on the second serve will be critical to beating Serena Williams.

Breaking Williams' serve is difficult enough, but the 24-year-old Belarusian will get into serious trouble if she can't make the most of her service games. 

In the semifinals, Azarenka struggled to get her first serve in play, putting just 56 percent into the box. She would win 57 percent of those points but wound up winning just 34 percent of her second-serve points. 

Obviously, that percentage will need to be much higher against Williams as pointed out by The New York Times' Ben Rothenberg on Twitter:

Starting Fast

Victoria Azarenka can't wait until the second set to get going in Sunday's final. Serena Williams is too talented an opponent to fall behind against.

Sure, Azarenka dropped the opening set against Williams in Cincinnati only to storm back and win the title. But that was the first time Azarenka had ever beaten Williams after losing the first set, and is unlikely to happen again.

Quite frankly, the more room for error she gives Williams, the smaller her chances of winning.

On the other hand, a fast start could put Williams on her heels and force her to start pressing and taking more risks. More risks mean more errors and more easy points for the two-time Aussie Open winner.

Follow Bleacher Report Featured Columnist Patrick Clarke on Twitter.