LONDON (AP) ― As the rain wreaks havoc on the Wimbledon schedule and players start to complain, Andy Murray and Novak Djokovic have found little reason to worry about the weather.

It helped that both got to play Monday on Centre Court, the only spot at the All England Club with a retractable roof.

And with back-to-back, straight-set victories, they moved closer to a semifinal showdown that would be a rematch of the final last year, when Murray beat Djokovic to become the first British man since 1936 to win Wimbledon.

“Sometimes the scheduling works in your favor. Sometimes the weather works in your favor,” Murray said. “You just have to deal with it.”

He reached the quarterfinals for the seventh consecutive year by dulling the dangerous serve of 20th-seeded Kevin Anderson and saving a set point in the tiebreaker of a 6-4, 6-3, 7-6 (6) win. They played under a drizzle for about 15 minutes before the roof was closed early in the second set.

It stayed that way for the top-seeded Djokovic, and the 2011 champion beat No. 14 Jo-Wilfried Tsonga for the 11th consecutive time, 6-3, 6-4, 7-6 (5). Djokovic grimaced once in the final set while clutching the upper left arm he landed on in his prior match, but finished strongly and said afterward he felt fine.

“A lot of matches were canceled, but that’s London, that’s Wimbledon, with its very unpredictable weather,” Djokovic said.

Murray, who hasn’t dropped a set, said: “They should always try to play with the roof open, because it’s an outdoor event.”

Easy for him to say.

Australian Open champion Stan Wawrinka was less than pleased that his third-round match was put off from Saturday to Monday (Wimbledon tries to avoid playing on its middle Sunday). He got through it quickly, defeating 45th-ranked Denis Istomin 6-3, 6-3, 6-4 in less than 1 1/2 hours.

Afterward, the fifth-seeded Wawrinka noted it won’t be easy to win five best-of-five-set matches in a week if he’s going to claim the title.

“For sure, I was disappointed,” Wawrinka said about not getting on court Saturday, when showers disrupted play for several hours. “You cannot do anything. You have to accept (it). They do what they want, and you just follow.”

Asked whether he spoke with officials, Wawrinka said: “They just say what’s going to be the schedule and that’s it. Even if you want to talk to them, they’re not going to change anything. They don’t listen (to) the player. They just do what they think is good for them.”

All England Club spokesman Johnny Perkins said the process was explained to Wawrinka’s coach, including that having past major champions on larger courts is more of a priority than getting all matches completed on a given day.

The start of Week 2 at Wimbledon is called “Manic Monday,” because it usually has all 16 fourth-round matches after taking Sunday off.

“I understand why Wawrinka was complaining, because we have this tradition here of the middle Sunday. ... We have to rethink (that),” Djokovic said. “We all know that tradition is something that is nurtured here ... and we respect that. But there are some rules that I believe should be updated.”

Wawrinka will be on No. 2 Court on Tuesday ― when, by the way, the forecast calls for a slight chance of rain ― against No. 19 Feliciano Lopez, who eliminated the last American singles player, No. 9 John Isner, 6-7 (8), 7-6 (6), 7-6 (3), 7-5. It’s the first time in 103 years that no U.S. men or women reached the round of 16 at Wimbledon.

Like Wawrinka, Isner didn’t take well to having his match postponed. He tried protesting, to no avail.

“They had their reasons,” Isner said.

Maria Sharapova never got a chance to play at all Monday, because her fourth-rounder against No. 9 Angelique Kerber was postponed. That was rescheduled for Tuesday, and the winner must play Wednesday against No. 13 Eugenie Bouchard, the first Canadian in the Wimbledon quarterfinals in the 46-year Open era.

These quarterfinals are set: Murray vs. No. 11 Grigor Dimitrov, and Djokovic vs. No. 26 Marin Cilic in the men’s bracket; 2011 champion Petra Kvitova vs. Barbora Zahlavova Strycova, and No. 22 Ekaterina Makarova vs. No. 23 Lucie Safarova in the women’s.

Bouchard advanced with a 7-6 (5), 7-5 victory over No. 25 Alize Cornet, the Frenchwoman who beat Serena Williams.

“I believe in myself. Every match I play, I believe I can win,” said the 20-year-old Bouchard, the only woman who was a 2014 semifinalist at the Australian Open and French Open. “I’ve proved to myself I can play on the big stage.”