U.S. Open 2015 live stream, semifinals times, TV: Roger Federer, Serena Williams, Novak Djokovic to play

After the U.S. Open tennis women's semifinals were delayed a day Thursday due to rain, Friday shapes up to be a day to remember -- with men's and women's semifinals matches that include Roger Federer, Novak Djokovic, and Serena Williams.

The U.S. Open tennis semifinal times for today (Friday) includes:

Women's semifinals singles 10 a.m. central/11 a.m. eastern: Flavia Pennetta vs. Simona Haslep, followed by Serena Williams vs. Roberta Vinci.

Men's semifinals singles 4 p.m. central/5 p.m. eastern: Novak Djokovic vs. Marin Cilic, followed by Roger Federer vs. Stan Wawrinka.

TV channel: ESPN.

To watch the U.S. Open tennis semifinals online via live stream, visit Watch ESPN. You will need a cable subscription or access to someone's cable subscription sign in to watch.

Friday semifinals matches preview

More than three years have passed since Roger Federer last won a Grand Slam title.

That's not to say he hasn't played well in the meantime: As he likes to point out, it takes some doing just to make it to the latter stages of a major tournament, and Federer has managed to continue to do that.

His seemingly effortless trip to the U.S. Open semifinals — Federer has won all 15 sets he's played entering Friday, dropping only 44 games along the way — marks his sixth run to that round in the past 11 majors.

And yet when Federer was asked about being two wins away from grabbing another trophy, he noted that there is plenty of work left.

"Hours of work and sleeps and waits and nerves and all that. It's still a long way," Federer said. "I feel like I'm close, of course. You enter now a territory which is very interesting."

On Friday, the No. 2-seeded Federer will face No. 5 Stan Wawrinka in a matchup pitting a pair of pals who won a gold medal for Switzerland in doubles at the 2008 Beijing Olympics. That will come after No. 1 Novak Djokovic meets No. 9 Marin Cilic, the defending champion.

They form quite a quartet.

It's the first time since 1995's group of Pete Sampras, Andre Agassi, Jim Courier and Boris Becker (who now happens to coach Djokovic) that all of the U.S. Open men's semifinalists have won a Grand Slam title.

Federer, of course, leads the way among this year's foursome with a record 17, including five in New York.

Djokovic has won nine major titles, including at the Australian Open and Wimbledon this season, but despite reaching his ninth consecutive semifinal at the U.S. Open, he's only left with a trophy once, in 2011.

Wawrinka is a two-time major champion, including at the French Open in June.

And Cilic's only appearance in a Grand Slam final came at the U.S. Open a year ago.

"These guys that are left in the tournament," Cilic said, "they are very dangerous."

None has looked better, match in and match out, than Federer so far. He has won 67 of his 69 service games, saving 9 of 11 break points. Only one opponent, 29th-seeded Philipp Kohlschreiber in the third round, managed to break Federer.

Only once before, at the 2011 U.S. Open, has he dropped as few as 44 games on the way to a major's semifinals without getting the benefit of a retirement or walkover.

And only once, at the 2007 Australian Open, has Federer won a Grand Slam title without losing a set.

Now he takes on Wawrinka for the 20th time. Federer is 16-3; all of Wawrinka's head-to-head victories came on red clay, including in the quarterfinals at Roland Garros this year.

"I will, for sure, need to play my best tennis," Wawrinka said about facing Federer. "He's playing really well so far. He loves to play. He knows how to play. ... It's going to be a big challenge. I think I'm ready."

At least he's beaten his semifinal opponent. Cilic has lost every match against Djokovic, 13 in all.

"I'm sure he's not going to start coming to the net after every ball, but I'm sure he's going to try to be aggressive, going to try to take his chances. That's how he won last year's U.S. Open," Djokovic said. "I watched him play. He played great. Best tennis of his life. This is where he loves playing."

Here's what else to watch Friday at the U.S. Open:

WOMEN'S SEMIFINALS

Serena Williams' bid for tennis' first calendar-year Grand Slam since 1988 resumes Friday, when she plays 43rd-ranked Roberta Vinci of Italy in the semifinals. No. 2 Simona Halep faces No. 26 Flavia Pennetta in the other semifinal. Both matches were originally scheduled for Thursday night, but were postponed hours ahead of time because of rain in the forecast. Showers did eventually arrive, a little more than an hour before Williams and Vinci were supposed to begin.

The Associated Press contributed to this report.

Roger Federer’s new tactic could be difference vs. Stan Wawrinka

If possible, Roger Federer’s tennis is more entertaining now than during his heyday when he won five straight U.S. Opens. In an era when approaching the net is considered passe, here comes the 34-year-old Swiss Maestro, doing it better than ever.

Federer is trying to get back to his first Open final since 2009 and doing it his way — “the SABR’’ one of his inventions that could unlock the door.

Federer faces fifth-seeded Swiss countryman Stan Warwinka in a semifinal moved to smack in the middle of prime time because of the women’s semifinal postponement Thursday. Wimbledon champion Novak Djokovic, looking for his third major of 2015, will face defending Open champion/afterthought Marin Cilic in the first semifinal at 5 p.m., followed by the All-Swiss affair.

When notching most of his record 17 majors, Federer lessened his net work, letting his baseline game do the damage. He has tried to reinvent himself, going back to his net-loving junior days as he bears down on his first major since 2012.

“I think I’ve worked on my game moving forward, taking the ball earlier,’’ Federer said. “I think I’m volleying better than I have in the last 10 years. I was volleying well coming up on the tour when I was young. Now because my serve is working quite well, you put those two things together and standing in on the [service] return, it has changed the dynamics.’’

Federer came into the Open on a roll and with a new shot — rushing to the service line to take early an opponent’s delivery and following it to the net. His exquisite play in winning in Cincinnati and downing Djokovic, who beat him in the Wimbledon finals, had many predicting a sixth Open title.

Federer already was envisioning a new silver trophy, suggesting to tournament officials the past winners should be engraved on each new chalice.

“I love tennis history and I like to see who has won in the past,’’ Federer said. “I would like to have another one.’’

Federer traces a rebirth to finally mastering the change to a larger racket frame he made more than a year ago. He found himself hitting his backhand more cleanly.

“I think I’m taking the right decisions at the right times,’’ Federer said. “I think the racket is helping me, easier power. Now having played with it for over 1 ½ years, I feel like I’m really finding the zones, where to hit them. I can place it more accurately right now than I ever could.’’

The late-blooming Wawrinka, who has as many major titles as Andy Murray (two), beat Federer at the French Open and knows his buddies’ game well. Wawrinka’s girlfriend, Donna Vekic, in the middle for the Nick Kyrgios controversy, has attended Wawrinka’s matches. But she may not be rooting for a winner, considering Federer’s 16-3 record against her boyfriend.

“It took him a while to figure out exactly what his possibilities are,’’ Federer said. “I don’t think he’s a guy who had enough confidence. He definitely is a big test and big challenge for me. Subconsciously you know [that] he knows what your preferences are.’’

In the undercard, Cilic takes a 12-match Open winning streak into the Djokovic showdown but has never beaten the Serbian (0-13), including a 6-4, 6-4, 6-4 defeat in July at Wimbledon. Cilic, from Croatia, is a heavy underdog.

“It’s the toughest matchup,’’ Cilic said. “I had close matches last few years, but I haven’t found the right formula to win.’’

But they haven’t met at Arthur Ashe Stadium.

“This is where he loves playing,’’ Djokovic said. “He loves the conditions on Arthur Ashe. I’m going to try to use that advantage and having success against him in the past and to my favor.’’