This Swiss is on roll, but far tougher challenges are in store

The Swiss No.1 has played just one match on SW19's two main arenas this fortnight, less not only than the nominal 'big four' of the men's game - including his countryman Roger Federer - but also Grigor Dimitrov and Jo-Wilfried Tsonga, two men who have yet to win a slam and by the rankings at least, are not even in the world's top dozen.

To compound it all, as the afternoon's rain cleared on Saturday, Wimbledon organisers decided against rescheduling his match against Uzbekistan's Denis Istomin. This left Stan needing to come through three matches in three days, and five in seven, if he is to add the SW19 title to the slam he captured at Melbourne Park.

Clad in a T-shirt bearing the legend 'Stan the Man' - perhaps such pithy sound bites are required to remind everyone of his existence - the 29-year-old accused the organisers of intransigence after he completed the first leg of his arduous run in a surprisingly straightforward fashion, his Usbek opponent dismissed 6-3, 6-3, 6-4 out on Court No.2.

His countryman Federer is one man who lies in his path, but having equalled his best-ever Wimbledon run at this slam, Wawrinka first faces Feliciano Lopez, a Spaniard who will at least be as tired as he is.

"For sure I was disappointed," Wawrinka said, recalling his emotions when he learned that Saturday's match would not go ahead. "To play any five-set match is never easy. But me or Lopez will have to play three five-set matches in three days. It's terrible for the body.

"I was expecting them to move matches," he added. "To move maybe juniors or doubles, to make my match or Lopez's third-round match against John Isner first on when it stopped raining and they started up again at 5pm or 6pm.

"But then you just have to accept it. 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."

Even when fit and given a fair crack by the organisers, Wawrinka's inability to make inroads at this tournament remains one of the mysteries of modern tennis.

Even Istomin had won the only previous meeting between these two on a grass court, a first-round victory back in 2010.

"It's not the surface on which I have had the best results," he admitted. "But I still love to play on grass. I've had more time before the tournament to get ready. I'm taking it match after match and we'll see.

"Now I'm going to take some treatment and rest and get ready for tomorrow."

This Swiss was on a roll, and the plain speaking continued on the theme, introduced into the conversation by Roger Federer, of having a basketball-style 25-second shot clock between points.

"One year ago, the ATP start to have a strict rule about the 25 seconds, but it lasted for what?" asked Wawrinka. "How many times can you see some players taking more time than the 25 seconds, getting one time violation, that's it?

"After playing for three hours, you can see on TV that sometimes the average time is 28 or 30 seconds. If you want to put a rule, then make it strict for all the players. A shot clock would be interesting and good to see."

At least Wawrinka got his match out the way before the rain came down. Precipitation was battering away on the translucent roof of Centre Court as Novak Djokovic made light work of Jo-Wilfried Tsonga by a 6-3, 6-4, 7-6 (5) score.

A Serb-Croat derby awaits in the quarter-finals with Marin Cilic, the No.26 seed and conqueror of Tomas Berdych, who added Jeremy Chardy to his list of vanquished opponents. Djokovic has won all nine previous meetings but is not counting his chickens. "It plays maybe a little bit in my favour, but he is now working with Goran Ivanisevic and he has improved a lot, especially his serve which is important on this surface," said the Serb.

Earlier, Kei Nishikori got the better of Simone Bolelli in a restarted match to complete the fourth round.