A quick look at the U.S. Open :
LOOKAHEAD TO WEDNESDAY
Maria Sharapova plays in the second round in Arthur Ashe Stadium against Timea Babos, trying to follow up on her upset of No. 2 seeded Simona Halep on Day 1.
Sharapova is a five-time major champion, including at the 2006 U.S. Open, and a former No. 1 who needed a wild card from the U.S. Tennis Association to get into the field after a 15-month doping suspension caused her ranking to plummet.
Babos, meanwhile, is ranked 59th and has only once made it as far as the third round at a Grand Slam tournament, getting to that stage at Flushing Meadows a year ago. She lost in the first round at the other three majors this year.
Other past major champions in action Wednesday include Venus Williams (against Oceane Dodin of France) and Juan Martin del Potro (against Henri Laaksonen of Switzerland).
The night's final match in Ashe is intriguing: No. 8 seed Jo-Wilfried Tsonga of France, the runner-up at the 2008 Australian Open, against 18-year-old qualifier Denis Shapovalov of Canada. Shapovalov became the youngest man to reach a Masters semifinal, doing so this month at a hard-court tournament in Montreal.
Sunny. High of 81 degrees (27 Celsius).
Rain. High of 68 degrees (20 Celsius). All but nine matches were postponed to Wednesday.
Seeded winners in the men's first round: No. 1 Rafael Nadal, No. 3 Roger Federer.
Seeded winners in the women's first round: No. 1 Karolina Pliskova, No. 12 Jelena Ostapenko, No. 15 Madison Keys, No. 23 Barbora Strycova.
Seeded losers in the women's first round: No. 6 Angelique Kerber, No. 28 Lesia Tsurenko.
STAT OF THE DAY
2 - Number of defending women's champions at the U.S. Open who have lost in the first round in the professional era, which began in 1968: Angelique Kerber on Tuesday and Svetlana Kuznetsova in 2005.
QUOTE OF THE DAY
''All the noise stays inside and this is difficult.'' - Rafael Nadal, complaining about how loud it is in Arthur Ashe Stadium with the roof closed.
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