NEW YORK -- Here are the storylines and matches to watch on Day 5 of the U.S. Open. Tennis Channel begins its coverage at 11 a.m., and ESPN2 picks up coverage at 1 p.m. Click here for the order of play.
Sloane Stephens and Jamie Hampton in All-American battle: I wrote before the tournament that the Americans generally had horrible draws this year. We'll start to see that come to fruition now. American No. 2 Stephens, the 15th seed, takes on American No. 3 Hampton, the 23rd seed (third match, Arthur Ashe Stadium), in the third round for the right to possibly meet American (and world) No. 1 Serena Williams in the fourth round. Stephens and Hampton are matched up for the second Grand Slam tournament in a row; Stephens won 6-3, 6-3 in the first round of Wimbledon and leads the head-to-head 2-1.
For Hampton, this is a new situation. This is her fourth U.S. Open main draw and she just recorded her first victory this week. Seeded for the first time at a Slam, Hampton broke out into a huge grin when asked about how it felt to live up to her seeding but admitted it's tough playing someone she knows so well. Stephens agreed.
"It's always tough playing another American," Stephens said. "Jamie is a good friend. Obviously it will be a good match. Playing at the U.S. Open, it's a pretty big deal. I'm looking forward to it. I'm excited."
Li Na goes for revenge against Laura Robson: Last year, in this very round, Robson, then ranked No. 89, stunned Li 6-4, 6-7 (5), 6-2. A year later, Robson is seeded here (No. 30) and the two will meet again (first match, Arthur Ashe Stadium). It was a tough loss for Li, who was in good form after making the Montreal final and winning Cincinnati weeks before. For Robson, it was another big victory after sending Kim Clijsters into retirement in the previous round. On form, you have to like the fifth-seeded Li, especially with Robson nursing a wrist injury. But given Robson's ability to raise her level on the biggest stages and Li's inconsistency, it's a tough one to call.
Top seeds in action: Novak Djokovic should cruise past Germany's Benjamin Becker in the second round (second match, Arthur Ashe Stadium), while Serena WIlliams takes on Yaroslava Shvedova (second night match, Arthur Ashe Stadium) in the third round. Shvedova pushed Williams deep into a third set last year at Wimbledon before losing 6-1, 2-6, 7-5 in the fourth round. Could be a tricky one.
Matches to watch
Lleyton Hewitt vs. Juan Martin del Potro (first night match, Arthur Ashe Stadium): Hewitt is always a dangerous early-round opponent. But he didn't look great in his opening win over Brian Baker, in which Hewitt was broken seven times in four sets. Del Potro is the obvious favorite, but it will be fun to see if the 32-year-old Australian can conjure up any magic under the lights on Ashe.
Stanislas Wawrinka vs. Ivo Karlovic (fourth match, Court 11): Karlovic came back from two sets down to knock James Blake into retirement in the first round. He's been playing well, qualifying for the tournament with three good wins. Wawrinka, the ninth seed, hasn't won back-to-back matches since mid-June and sustained a back injury while playing on clay in July. An upset wouldn't surprise me.
Ekaterina Makarova vs. Sabine Lisicki (second match, Grandstand): Considering she stunned Williams at WImbledon and went on to make the final there, it's a bit surprising how under the radar Lisicki has been ever since. Lisicki, the 16th seed, limited her post-Wimbledon schedule because of a wrist injury, but she's looked good through her first two rounds. Makarova, a lefty seeded 24th, who upset Williams at the 2012 Australian Open, will be Lisicki's first real test. Donald Young vs. Florian Mayer (third match, Grandstand): Raise your hand if you did a double-take upon seeing Young, who's dropped to No. 157, defeat Martin Klizan, who made the fourth round last year, 6-1, 6-0, 6-1 in the first round. Confident after a successful qualifying campaign, the 24-year-old American will have to be ready for Mayer's unorthodox game. If you like slice backhands, tune in to this one.