Williams, who came into the U.S. Open 60-4 with eight singles titles this year, has yet to lose a set in the tournament, most recently disposing of seeded players Sloane Stephens, Carla Suarez-Navarro and Li Na. She also owns a 12-3 lifetime mark against Azarenka.
Of course, Azarenka has won two of their last three meetings, emerging victorious in Doha and Cincinnati this year. The 24-year-old also came into the U.S. Open 36-4 with two singles titles this year.
Where: USTA Billie Jean King National Tennis Center in Flushing Meadows, N.Y.
When: Sunday, Sept. 8 at 4:30 p.m. ET
Azarenka has dropped just two sets in six matches at the U.S. Open this year. That includes disposing of dangerous underdog Flavia Pennetta in straight sets in the semifinals.
Azarenka needs to take advantage of service games to topple Williams. In her two wins against the 31-year-old this year, she's won at least 56 percent of service points, via WTATennis.com. In her loss in Rome, she won only 43 percent of service points.
This is a rematch of last year's U.S. Open final. Williams defeated Azarenka in three sets in last year's final, 6-2, 2-6, 7-5.
While Azarenka has defeated all of her opponents thus far in straight sets, it's worth noting that she did struggle in some capacity, despite facing no seeded players. Against Pennetta, she won only 34 percent of second-serve points while posting six double faults to zero aces, per USOpen.org.
On the other hand, though it isn't always smooth sailing for Azarenka, she tends to get the job done. She's known for a being a gritty, tenacious player who can wear opponents down.
Matt Zemek, a columnist at College Football News who is also an avid tennis fan, tweeted:
This is the dream matchup most fans wanted. Azarenka has handed Williams two of her four losses this year, and the Belarusian has shown she's not intimidated by the historic American.
Looking ahead to the match on Sunday, Azarenka said, according to the Associated Press, via ESPN.com:
We know each other pretty well. I know her strengths; she knows my strengths. That's what it's all about, about those turning points, who wants it more, who's willing to go for it more.
Azarenka won the Australian Open this year. Williams won the French Open. And the top two women's players in the world will battle for the 2013 U.S. Open crown on Sunday.
Could it get any better?
Prediction: Williams 6-3, 5-7, 6-4