LONDON — The so-called “Big 4” who have won 35 of the past 37 Grand Slam men’s singles titles — Novak Djokovic, Rafael Nadal, Andy Murray and Roger Federer — are all around for the second week at Wimbledon. They’re joined by the new major winner on the block, Australian Open champion Stan Wawrinka.

The same can’t be said on the women’s side, where top-seeded and five-time champion Serena Williams won’t see any action at the All England Club in Week 2 — except in doubles with sister Venus, another five-time Wimbledon winner who is also out of singles play.

With Serena Williams out and second-seeded Li Na also a third-round loser, it marks the first time in the Open era that the top two women’s seeds haven’t advanced to Wimbledon’s fourth round. Williams, who has 17 Grand Slam singles titles, hadn’t been knocked out of Wimbledon so early since 2005, but she has departed before the quarterfinals at four of the past five majors.

WTA founder Billie Jean King, winner of eight Grand Slam singles titles in the Open era, said she recalls going through a similar streak in her career.

“Most definitely,” King said Sunday. “Everybody does. But I think there might be some underlying things happening to her, some things off the court, that are affecting her. I’m sure she will work them out.”

On a sunny but blustery middle Sunday — traditionally an off day at Wimbledon — most of the players remaining in the singles draw held sessions at the nearby Aorangi Park practice courts.

Federer and Murray were there at the same time, although due to rain delays Friday, Federer, like Nadal, won’t play his fourth-round match until Tuesday.

Federer said he’s amazed as anyone about the Big 4’s ability to maintain such a stellar record in Grand Slam tournaments.

“I came through the ranks where it was normal for top guys to have a bad Slam, have maybe two bad Slams from time to time, but it barely happens anymore,” Federer said. “It’s like such a shock when it does. I think I’ve been surprised how consistent I’ve been personally, but even more so by everybody else who is just like normal to get to quarters, get to semis. Because I know how small the margins are.”

Djokovic’s chances of advancing might rest with his sore arm. He had an afternoon training session Sunday to test his left arm and shoulder he injured in a nasty fall Friday in his Centre Court win over France’s Gilles Simon.

Djokovic lunged for a shot behind the baseline, tumbled on the grass and rolled over twice, his racket flying from his hand.

He thought he had dislocated his shoulder, but from what he said, it looked a lot worse than it was.

“Luckily there is nothing damaged,” he said. “I’m quite confident that it will not affect my physical state or regimen or daily routine. I think it’s going to be fine.”

Djokovic will play the third match on Centre Court on Monday against 14th seed Jo-Wilfried Tsonga.

Alize Cornet, who scored the biggest upset of the tournament when she beat Serena Williams on Saturday, opens Monday’s play on Centre Court against Canadian Eugenie Bouchard, who is the only woman to advance to the semifinals of both Grand Slam tournaments this year.

Defending champion Murray plays Kevin Anderson in the match following.

In third-round matches carried over after Saturday’s rain suspensions, Wawrinka is up against Denis Istomin to start play on Court 2 while Feliciano Lopez plays John Isner on Court 3.

The only other third-round men’s match to be completed is nearly there — Kei Nishikori of and Simone Bolelli are 3-3 in the fifth set, with the winner to play Milos Raonic on Tuesday.