It is a measure of the Scot’s progress through this championship that, after a 6-4, 6-3, 7-6 fourth-round victory over Kevin Anderson yesterday in which he reached new heights, he was also more self-critical than before. His play, he said, had dropped a notch or two when the roof was closed and the match resumed under the closed Centre Court roof. He was right – it had, but only so far as to allow the No 20 seed one solitary set point. Anderson’s ranking this Wimbledon is a mere three places higher than Roberto Bautista Agut, the man Murray brushed aside in the previous round, but this was a significantly stiffer challenge for the champion. Not only does the 6ft 8in South African have a seriously intimidating serve, he is also far more mobile than other giants such as John Isner and Ivo Karlovic. And yet Murray dealt with that threat in at once a rational and an inspired manner, to go through to a quarter-final meeting with 11th seed Grigor Dimitrov. “Everything was going my way when we stopped, and then it’s different conditions,” he said in his post-match press conference. “He started hitting the ball cleaner. I started off a bit tentative when we came back out. But, you know, I still did well. I still created loads of chances, a lot of opportunities in the third set, and just couldn’t quite get them. “But, I mean, I still played pretty well under the roof. I was just a little bit more tentative and he was going for his shots a little bit more. “I knew I was going to get tested at some stage. And today I was pushed, especially in the middle part of that second set, then obviously later on in the third there were some tight moments. But I handled them fairly well. It was a good match.” While Murray became the second man through to the last eight after Marin Cilic, his biggest rivals are lagging behind in the schedule because of the rain. No 5 seed Stan Wawrinka, for example, only won his third-round match yesterday, and now faces playing on three consecutive days. “Sometimes the scheduling works in your favour,” Murray added. “Sometimes the weather works in your favour. 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 [Martina] 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’ve had a two-day break and will be fresh for that. You know, if you can get through that period, you’re going to be feeling pretty sharp and pretty good, so you just have to get on with it.” Anderson, at 28, playing the best tennis of his career, praised the almost telepathic way in which Murray reads his opponents’ serves. “My biggest strengths, he definitely neutralises a lot better than other play, starting with the return of serve,” the South African said. “He reads it really well. “He was moving great – that’s a big part of his game. Grigor is going to have to play very well if he wants to beat Andy.” Sir Alex Ferguson, the man Murray credited with offering some “gold dust” advice last year, was in the Royal Box yesterday and had a brief meeting with his compatriot after the match. “Not for long, but just immediately when I came off the court, I had a little chat to him,” Murray explained. “We stay in contact throughout the year. “We chat about a lot of things. We talked about my match today, spoke about football, World Cup a little bit. Then he just said a few things, what he’s observed when he’s been watching me, not necessarily about technical or tactical things, but more sort of mental things, how you respond to tough or tight situations.” A follow-up question provoked a less expansive answer. Would he consider employing Sir Alex as part of his coaching team? “No,” he said. “I wouldn’t see that happening.” Murray was also asked about Alex Salmond’s impromptu display of a Saltire in the Royal Box at the end of last year’s final against Novak Djokovic – a gesture that has previously been mildly criticised by the champion. “I’m not getting into that nonsense during the tournament,” was his reply. It has, indeed, been a very no-nonsense campaign by Murray so far. No loss of focus. No drop in form. No distractions. Just an unshakable determination to hold on to the trophy he won so memorably last year.