NEW YORK -- Here are the storylines and matches to watch on Day 6 of the U.S. Open. CBS begins its coverage at 11 a.m and Tennis Channel picks up the night session at 7 p.m. Click here for the order of play.
John Isner returns to Louis Armstrong Stadium: Don't worry, John, the crowd will be close to 100 percent behind you this time. Isner looks to avenge his five-set loss to Philipp Kohlschreiber last year in the same round to make the fourth round of a Grand Slam tournament for the first time since the 2011 U.S. Open. Last year, Isner lost his cool as he wasted a two-sets-to-one lead in a match that finished after 2 a.m. ET on Arthur Ashe Stadium.
"It's crazy, playing him in the third round just as I did last year at this event," Isner said after his second-round win over Gael Monfils. "That match last year was very disappointing for me how it went about. I sort of lost it ‑‑ I lost it in the fifth set there, but he's extremely solid. He's been so solid for so long now."
The two haven't played since. Kohlschreiber has pulled off a good number of upsets at majors, including wins over Novak Djokovic at the French Open and Andy Roddick at the Australian Open.
Roger Federer watch: It used to be that you could write Federer's name into the quarterfinals and just monitor his first-week results for pure entertainment. But after the year he's had and his early-round loss at Wimbledon, every match is one to key on. You just never know anymore. Federer faces 63rd-ranked Adrian Mannarino (against whom he's never lost a set in two meetings) in the second night match on Arthur Ashe Stadium. Mannarino is coming off a good win over Sam Querrey in the second round, and the Frenchman had a surprising run to the fourth round of Wimbledon two months ago.
Young Americans gunning for upsets: Jack Sock, 20, has done well to back up his third-round showing last year. He'll face Janko Tipsarevic (second match, Grandstand), who has slipped to No. 21 in the rankings after a horrendous year. Before this week, Tipsarevic hadn't won back-to-back matches since the French Open. With the way the draw has opened up (Sock avoided first-round upset victim Jerzy Janowicz in the second round), this is a great opportunity for Sock to make the fourth round of a Slam for the first time.
On the women's side, 23-year-old Alison Riske takes on the always unpredictable Petra Kvitova (first match, Court 17). Riske hasn't dropped a set in two rounds, which also happen to be her first two victories in the main draw of the U.S. Open. If Kvitova is playing well, this won't be close. But given that the seventh-ranked Kvitova has played three-setters in half her matches this year, who knows.
Christina McHale, who is in the third round of a Slam for the first time since being diagnosed with mono last summer, takes on No. 13 seed Ana Ivanovic (first match, Arthur Ashe Stadium). Ivanovic has been impressive through the early rounds, and unfortunately for McHale, the 11 a.m. start time means Ashe will probably be mostly empty when the match begins. The 21-year-old from Teaneck, N.J., may be shy, but she loves the support of the crowd at the U.S. Open. The lack of energy in the stadium at that time of the day will be tough.
Matches to watch
Feliciano Lopez vs. Milos Raonic (second match, Court 17): Raonic hasn't dropped a set in two matches, and the pinched nerve that seemed to hamper him in Montreal and Cincinnati looks to have been resolved. He faces his good friend Lopez in what will be a battle of big servers. Drawn into a weak section that has been decimated even further with the losses by Ernests Gulbis and Janowicz, Raonic has a very makeable path to the semifinals. Svetlana Kuznetsova vs. Flavia Pennetta (first match, Court 11): What is it, 2009? These two veterans have slipped in the rankings because of injury, but this is a throwback match that should entertain WTA fans. Pennetta knocked out fourth-seeded Sara Errani in the second round, while Kuznetsova came through in three sets over Peng Shuai. The Russian, ranked No. 27, is 5-0 against Pennetta.