Three main matches highlighted Day 12's action at Arthur Ashe Stadium, but there was plenty of excitement throughout the day.
Here's a quick look at the scores from the biggest matches of the day, followed by additional analysis and highlights.
Max Mirnyi and Andrea Hlavackova Win Mixed Doubles Title
The first big match of Day 12 at the 2013 U.S. Open pitted Max Mirnyi and Adrewa Hlavackova against Abigail Spears and Santiago Gonzalez in the mixed doubles final.
Spears and Gonzalez nearly stole the first set, but Mirnyi and Hlavackova buckled down to win on their third tiebreak chance, as shown by US Open Tennis:
The winning team held off eight of nine break-point attempts in that first set, taking advantage of a flurry of mistakes by their opponents.
The second set wasn't nearly as competitive, as Mirnyi and Hlavackova sharpened up their attack and won easily, 7-6(5), 6-3, as noted by Live Tennis:
While many casual fans don't know who Mirnyi is, he hit an impressive benchmark with the victory. As noted by USPTA New England, it was Mirnyl's 10th career Grand Slam victory:
Ten Grand Slam titles is a goal most professional tennis players will never achieve. Hitting this mark shows what kind of relentless work he's put into his craft over the years, and it's an accomplishment that should be lauded.
Victoria Azarenka Shows Mental Toughness to Reach Final
Heading into the semifinals, there was no doubt who was favored in the matchup between Azarenka and Flavia Pennetta. Azarenka is the No. 2-ranked player on the ATP, while Pennetta is ranked No. 83.
Easy call, right?
Not so fast.
In the end, Azarenka prevailed in straight sets, 6-4, 6-2, as noted by US Open Tennis, but her victory wasn't of a dominant nature, as SI.com's Jon Wertheim pointed out afterward:
The pesky Italian was able to convert five of six break point opportunities and outdid her opponent in winners, hitting 19 to Azarenka's 15.
The Belarusian kept her composure throughout the match and showed some serious mental toughness to win. It'll take more of the same when she faces Serena Williams, who was far more dominant in her semifinals match.
Serena Williams Looks Unstoppable
Williams is on one of her legendary tears right now.
In six matches since the start of the U.S. Open, she has only lost 16 total games and hasn't come close to losing a set.
While it's true the No. 1 player in the world faced a few easy opponents early on, her last three matches have been against top-20 players, and Li Na is hardly a slouch at No. 5 in the world.
But when Williams stepped on to the court against Li, there was no doubt about which player was the more talented. Williams jumped out with a perfect first set, converting three of three break-point chances to win 6-0.
Li was determined not to get run over in the second set and won three hard-earned games, but her attempt to defeat Williams ended in disappointment. The final score was 6-0, 6-3, as noted by US Open Tennis:
These two finalists have met 15 times in the past, with Williams winning 12 of those matches. Williams will be heavily favored to beat Azarenka in the final, but it's worth noting that the Belarusian star has won two of the last three matches.
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