GRAND slam campaigns can be draining for players and this fatigue is not restricted to the results of their efforts on courts.

The trials of Wimbledon on Andy Murray are constant but none can be more tedious than the matter of expectation. Every press conference is marked with a variation on "how near are you to a breakdown, Andy?"

The post-match interview after Murray had defeated Mikhail Youzhny conformed to script. Inevitably, someone asked the question. It came in this form: how much pressure do you feel right now coming towards the end (of the tournament, presumably, not existence)?

Murray replied: "Do you want it in words, a number, or percentage?"

It was a perfect example of the Scot's wit that is as dry as a slice of toast at a Saharan buffet. He gave the questioner a number – "a seven or an eight" – and the matter was laid to rest until the next time he faces the press.

The truth is that pressure will not be the deciding factor on whether the Scot wins the Wimbledon title. He is a major winner, an Olympic gold medallist, a serial finalist in majors. This is what he does. He will be nervous and makes no secret of that, but the three obstacles that keep him from breaking the 76-year drought of a British winner of the men's singles can be encapsulated in three categories: injury, upset or Novak Djokovic.

The injury front is the hardest to evaluate. Murray moved with some caution against Youzhny on Monday and clutched his hip on occasion. He finished a practice session at Wimbledon yesterday with a brisk "Back's fine". He had extended treatment after the match against Youzny but was relaxed when hitting yesterday. He may be in top-notch condition but he will not tell anyone outside his circle if he is not. The best hope is that Murray was suffering from stiffness on Monday and he will back to full fluency of movement today.

Even if his fitness stands up, Murray must overcome the threat of an upset. He faces a left-hander in Fernando Verdasco today, the first southpaw he has played this year. However, the Spaniard should not present an overwhelming difficulty. Murray prepared yesterday by fending off left-handed serves from Johan Brunstrom, a 33-year-old Swedish doubles player. "He is playing great" was the succinct verdict from Brunstrom.

Murray also reflected on his defeat by Verdasco at the Australian Open in 2009. "It was a tough loss for me because I hadn't lost to him before and at the time it didn't look like a great result," said the world No.2. "But he went on to have a great year; he nearly beat Rafa in the semis there. It was a great match and it was very close. And he went on to finish the year in the top 10, so it wasn't such a bad loss."

It is also Murray's only defeat in nine meetings with the 29-year-old Madrileno, who has slipped to 54th in the world.

If this hurdle is negotiated, Murray would play Jerzy Janowicz (world No.22) or Lukasz Kubot (No.130) in the semi-finals. At Wimbledon 2013, where there have been so many shocks there is a suspicion that the top seeds were auditioning as lightning rods, Murray is aware that there is a possibility he could join the list of premature departures.

However, there is nothing in his record or in his performances at Wimbledon so far to suggest this is a probability. Murray is now a factor in the final stages of majors. In his last four appearances at the US Open, he has reached fourth round, third round, semi-final, and then won it; in Paris, the record is quarter-final, fourth round, semi-final, quarter-final; in Australia, it is final, final, semi-final, final; at Wimbledon, it is semi-final, semi-final, semi-final, final. And he has also won an Olympic gold on Centre Court.

Murray, too, rarely loses to players outside the others in the Big Four in slams, although David Ferrer defeated him in the quarter-finals in Paris in 2012, and this observation raises the prospect of a final with Novak Djokovic.

"There have been some great performances from me, I'm having a fantastic tournament and playing really well," said Djokovic yesterday, strengthening the impression the world No.1 is not a martyr to self-doubt. He plays Tomas Berdych today and will face either Juan Martin Del Potro or Ferrer in the semi-finals.

Djokovic poses a substantial threat to every other contender's hopes of ultimate success. He has been almost absurdly good at Wimbledon this year, dismissing such as Jeremy Chardy and Tommy Haas as if they were just decent club players.

The world No.1 is moving with an assurance that is marked by fleetness of foot and power of shot. He is a former Wimbledon champion and defeated Murray in Australia in the first grand slam event of the year. He is, justifiably and undoubtedly, the favourite. Murray, though, is a viable contender. In a week of great expectations, do not expect him to settle for that without the most debilitating of efforts.