| By Eric C. Peck
Photo credit: Kenneth B. Goldberg

Action at the 2011 U.S. Open will be light on Tuesday, as the Round of 16 will be further reduced and the women's singles quarterfinals will take center stage at the USTA Billie Jean King National Tennis Center. The first women's quarterfinals match will feature the unseeded German Angelique Kerber take on the number 26 seeded Italian Flavia Pennetta at Louis Armstrong Stadium. Kerber has had victories over the unseeded Romanian Monica Niculescu, Russia's Alla Kudryavtseva, 12th-seeded Agnieszka Radwanska from Poland and unseeded American Lauren Davis to reach the quarterfinals. Pennetta's path to the quarterfinals included wins over the 13-seed Shuai Peng from China; a huge upset over the number three seed, Maria Sharapova from Russia; the unseeded Italian Romina Oprandi; and an opening round win over France's Aravane Rezai.

Following the Kerber-Pennetta match at Louis Armstrong Stadium, the other women's singles quarterfinals match will feature Australian Samantha Stosur, the number nine seed, taking on number two-seeded Russian Vera Zvonareva. Stosur's wins at the 2011 U.S Open includes knocking off both the number 25 and 24-seeded Russians, Maria Kirilenko and Nadia Petrova respectively; unseeded American Coco Vandeweghe; and an opening round win over Sweden's Sofia Arvidsson.

At Arthur Ashe Stadium, the men's side of the draw will feature matches between unseeded American Donald Young taking on the number four seed, Andy Murray; followed by the unseeded Gilles Muller of Luxembourg taking on the number two seed, Spain's Rafael Nadal; and a nightcap under the lights featuring the number 21 seed American Andy Roddick facing Spain's David Ferrer, the number five seed.

Also under the lights at Ashe, a mixed-doubles semifinals match between the upstart unseeded American duo of Melanie Oudin and 18-year-old Nebraska native Jack Sock taking on the seventh-seeded team of Russia's Elena Vesnina and India's Leander Paes. Oudin & Sock's path to the mixed-doubles semis includes wins over the Czech Republic's Barbora Zahlavova Strycova & German Philipp Petzschner; a 2-6, 6-3, 1-0(10-6) win upset over the top-seeded mixed doubles team of the United States' Liezel Huber & Bob Bryan; and their opening round win over Vladimira Uhlirova from the Czech Republic and Slovakia's Filip Polasek.

Fans and players at the Open dodged a bullet Monday, as thunderstorms and rain were in the forecast, but the weather held up for all of the matches to be completed. Tuesday is a different story, as there is a 70 percent chance of rain as Day Nine action begins at 11:00 a.m. and a 70 percent chance of precipitation the rest of the day.

Click here for the full schedule of matches for Day Nine of the 2011 U.S. Open.

Eric C. Peck is Editor-in-Chief of Long Island Tennis Magazine. He may be reached by e-mail at eric@litennismag.com