One of the misunderstandings about sport is that opponents always compete under equal conditions. That understanding is housed in one of the great clichés which also comes from sport and speaks of a level playing field.

Yesterday as rain fell the players who rarely set a foot on Centre Court began to mumble about the inbuilt unfairness of court allocation and the impact of rain at Wimbledon.

From cutting the pitch to order for a home Test match in cricket to the scheduling at Major tennis tournaments there is often a bias and Wimbledon is no exception.

Stanislas Wawrinka, sporting an orange tee shirt with 'Stan The Man' emblazoned on the front, came off an outside court to face three matches in three days as Andy Murray and Novak Djokovic were appointed to Centre Court, where they could manage their time and rehabilitate their bodies according to schedule.

Wawrinka, as he sees it, unnecessarily carried a match over from Saturday, played it out yesterday and will play again today and tomorrow. It means if the world number three and current Australian Open Champion is to win his first Wimbledon title, he must play five best-of-five-set matches in a seven day window.

From Wawrinka's viewpoint the scheduling and the insistence on not playing any matches on the middle Sunday has given an unfair advantage to other players, namely those regulars, who appear on the roofed Centre Court, Andy Murray, Roger Federer, Novak Djokovic and Rafa Nadal.

Murray inadvertently made the point salient as he thundered through Kevin Anderson under the closed roof after Sunday's rest day with another rest day scheduled for today.

Wawrinka's coach, the former French Open champion, Magnus Norman, has called his players' disadvantaged position as 'almost inhuman' and he has a point.

Move matches

“For sure disappointed,” said Wawrinka. “First play five-set match it’s never easy. But if you look this week, me or Lopez have to play three matches in three days . . .five-set match that’s terrible on the body

“I was expecting them to move matches, move maybe juniors or doubles to make my match or Isner/Lopez match (on Saturday). But they took a decision and you cannot do anything. They just say what’s going to be the schedule and that’s it. They don’t listen to the player. They just do what they think is good for them.”

Wawrinka luckily finished against Denis Istomin yesterday just before more rain, coming through in straights sets 6-3, 6-3, 6-4 and faces Feliciano Lopez today. While his quiet rage was tempered by an unwillingness to place obstacles in his way, Murray was carefully dismantling the 6ft8in South African Kevin Anderson.

Again purring and once more needing only three sets, the defending champion was almost insouciant over the first set and a half. Mixing power with slower paced but placed balls, Murray delayed only after the roof was closed following rain and again in the third set when he was forcing the match to an end.

His game plan revolved around patience and once he broke Anderson’s serve the sets fell to him almost by appointment. He sped to 6-4, then struggled to 6-3 and again almost by design kept 15,000 people in their seats in a more troubled third.

Usually evenings like these involve hand wringing and swinging fortune as Murray’s tendency in the past was to create court demons and then rage against them, sometimes jeopardizing the match and always confounding the audience.

He seems to have cast that aside and while the match was tense and difficult Murray was finding magical shots whenever it seemed to drift, a sleeve of acutely angled forehand winner drawing gasps.

Rain delay

Anderson did play better after the early rain delay, was more aggressive and slowed an inevitable process down but the crowd were never taken to a position of doubting the outcome.

The third set tiebreak drew some emotion from Murray as Anderson earned a set point and threatened a fourth chapter. But Murray saved it and within seconds had engineered match point.

A deep backhand return out wide ended the match.

Unsurprisingly Murray found little appeal in fighting Wawrinka’s corner.

“Sometimes the scheduling works in your favour. Sometimes the weather works in your favour,” said Murray. “You just have to get on with it. It’s worked against me many times and many other players. You just have to deal with it.

“Someone told me the other day that Navratilova once played 17 matches in the second week, so I think we shouldn’t really worry about it. You’re going into possibly playing three days in a row best-of-five-set matches, but at least you have had a two-day break and will be fresh for that.”

Murray meets Grigor Dimitrov, a sparkling and athletic player, who will ask questions from him. Dimitrov steps into new quarter-final territory but his flashing game, which is both big and beautifully balanced will be Murray’s first major challenge of the competition.

Dimitrov won at Queens and with a rain delay yesterday beat Argentina's Leonardo Mayer 6-4, 7-6, 6-2. The Murray match will define him. The Scott knows he faces a Bulgarian way more dangerous than his 11th seeding.

Meanwhile, Djokovic’s left shoulder was in perfect working order as the top seed blasted past Jo-Wilfried Tsonga 6-3 6-4 7-6(5) to reach the quarter-finals for the sixth year running.