US Open WTA QF Previews: Serena vs. Pironkova, Azarenka vs. Mertens

There are players that come out of nowhere, and then there’s Tsvetana Pironkova. The Bulgarian, playing in her first tournament in over three years, has miraculously made the quarterfinals following upset victories over Garbine Muguruza, Donna Vekic, and Alize Cornet. If you go to Pironkova's WTA player profile page, there is no current ranking. If you try and find her current Universal Tennis Rating, you’ll find nothing.

While her incredible run will almost assuredly come to an end at the hands of Serena Williams on Wednesday, it remains one of the most unexpected, and impressive, Grand Slam runs in recent memory.

With a combined age of 70 years, this quarterfinal matchup is a testament to perseverance.

“It’s absolutely unreal, I really can’t believe it,” Pironkova said after her win over Cornet. “I was so exhausted by the end of the match, I really didn’t believe I had it in me, but I just kept fighting and fighting and obviously it paid off.”

Pironkova and Williams have faced off twice before during the 2015 season, with the GOAT capturing straight set victories each time. It’s safe to expect more of the same on Wednesday, but regardless of the result, the Bulgarian’s run to the quarterfinal is one of the most inspirational stories you will ever see at a tournament.

The Pick: Serena Williams

USTA

Elise Mertens will face off against a familiar foe in Victoria Azarenka on Wednesday, but for the first time on the singles court. Mertens and partner Aryna Sabalenka defeated Azarenka and Ash Barty twice last year, in the Miami Open semifinal as well as the US Open championship.

Prior to the resumption of the WTA Tour, Azarenka acknowledged a significant dip in her ambition during the lockdown.

"I don't know if I have a new appreciation for tennis," Azarenka told TENNIS.com. "I feel like my love for tennis has never really gone away. Motivation is something that can go up and down, and it went down a lot."

Whether Azarenka’s motivation increased, or she simply found her championship form once again remains to be seen, but the Belarusian has looked like her old self. With a win over Mertens, she will advance past the quarterfinals at a Grand Slam for the first time since 2013.

To get there, she’ll need to outlast arguably the WTA’s most solid player. The Belgian, who dismissed Sofia Kenin, 6-3, 6-3, on Monday night, has been brilliant since the tour returned. She reached the final in both Prague and Cincinnati (NYC), and has yet to drop a set in her first four rounds at Flushing Meadows.

According to the oddsmakers, this match is a complete toss-up, but according to UTR, it’s Mertens who owns the significant advantage. Judging by her form against Kenin, Azarenka is in trouble, but if there’s anything Pironkova (and Novak Djokovic) have taught us, it’s that anything can happen at this year's US Open.

The Pick: Elise Mertens