Stan Wawrinka has hit out at Wimbledon bosses for handing him five matches in seven days to achieve his title dream.

The fifth-seeded Swiss vowed to plough through his "tough" fixture pile-up after beating Denis Istomin 6-3 6-3 6-4 in Monday's rearranged third-round clash.

Wawrinka's match with Istomin fell foul of Saturday's rain delays, but the 29-year-old believes tournament organisers could have prioritised the clash over doubles or juniors contests and made a court available.

It was due to be played last on Court One on Saturday and eventually was contested on Court Two.

Wimbledon bosses have explained that crowd safety concerns stopped them shifting the world number three to an outside court at the weekend.

Wawrinka will face 19th seed Feliciano Lopez, who tiptoed past John Isner 6-7 (8/10) 7-6 (8/6) 7-6 (7/3) 7-5, on Tuesday after reaching the fourth round for the first time in five years.

"For sure I was disappointed," he said of Saturday's postponement. "If you look for this week, we have to play three matches in three days.

"Three five-set matches is terrible for the body.

"I was expecting them to move matches, move maybe juniors or doubles, to make my match or Isner-Lopez first on when they started again at 5pm on Saturday.

"They said they couldn't put us on an outside court because of safety issues, so then you just have to accept it. You cannot do anything, you just follow.

"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."

Wawrinka hailed his straight-sets victory over Istomin as the "perfect start" to his potential SW19 marathon.

"I know if I want to get through, it's going to be a really tough week," he added.

"I'm not looking about the final, I'm looking about the next match now.

"I was expecting a tough match today, but I did play really well.

"I'm happy with the way I'm playing, playing really aggressive.

"Winning in three sets, one hour 40 minutes, that was the perfect day, and the perfect start to this week."

Japan's Kei Nishikori completed his five-set victory over Italian Simone Bolelli to begin Monday's proceedings.

The 10th seed wound up his third-round clash 3-6 6-3 4-6 7-6 (7/4) 6-4, having been made to stop on Saturday midway through the final set.

Nishikori will face Canada's eighth seed Milos Raonic in the fourth round.

Marin Cilic stormed into his first Wimbledon quarter-final with a straight-sets win over Frenchman Jeremy Chardy, then hailed coach Goran Ivanisevic's influence.

Cilic said the 2001 Wimbledon champion has helped him put 2013's four-month drugs ban firmly in the past.

Cilic dispatched Chardy 7-6 (10/8) 6-4 6-4, then praised Ivanisevic for boosting both his confidence and form.

"The most important part for me was that I found some mental toughness out of all that," said Cilic of his comeback after his ban for taking outlawed stimulant nikethamide.

"When I came back it gave me more motivation to work and use every opportunity to be prepared for every tournament.

"I used that time for physical preparation as well.

"I didn't practise for three weeks maximum in that four months.

"I think my game is at a high level and it's becoming much more consistent day after day.

"Working with Goran has really helped build that confidence and that mental strength."