James Lawton: Novak Djokovic faces the big question - can he get any better?

Novak Djokovic plays an awkward shot during his quarter-final victory over Tomas Berdych (Getty Images)

As Andy Murray fought for his life and the hopes of the nation on Centre Court it was just as well he didn't have time to consider the latest measured thoughts of Novak Djokovic.

They were just a little chilling in the reach of their ambition and they followed hard on the kind of crisis management that separates not only great players from the merely good but also those who believe they are born to rule the world in one way or another.

Djokovic has been displaying this tendency of thought for some time now and he again produced the natural authority of a gunfighter while resolving a little pressure of his own.

Having lost two successive service games in the second set of his quarter-final with the world No 6 Tomas Berdych, the requirement was to remake himself as not only the man who has been dominating the imagination of this tournament these last few days but the entire world of tennis.

He did it, as he was expected to do on a Court One which seemed to be filled with an instinct to pay homage as much as applaud a riveting spectacle. Of course, Djokovic recovered his aura to win in three straight sets – he has still to drop one in this campaign – and claim a semi-final place against Juan Martin del Potro.

He did it with shots of astonishing accuracy and force and an instinct to seize the moments which inevitably overwhelmed the admirably hard-hitting man from the Czech Republic.

It meant that as Murray asked himself if he had the nerve to live with all the expectations suddenly put at risk against the ill-considered Spaniard Fernando Verdasco, Djokovic was facing another kind of issue. Inevitably, he was asked: can you get better?

"I believe you can always get better," said the 26-year-old, who is now irresistibly favoured to win his seventh Grand Slam title on the Centre Court on Sunday. "You know it's the kind of mindset I always try to have because you know that's something that keeps me going every single day on the practice courts, day in and day out, trying to give my best and trying to always, you know, inspire myself to play better tennis and improve in every way.

"I know I have quite a complete game but I still feel there is room for improvement. That's something that excites me for the future. I can't give you a number out of 10, I'm sorry, but I will say there's always something I feel I can do better."

The struggles of Murray against Verdasco were only briefly mirrored in the second-set scrape of the man who now looms so large over every ambition being taken to the line here in the old jousting lawns of SW19. His collapse to 3-0 down, having just brought a sharpened edge to the first set tie-break, was unaccountable and stunning, but then the drama disappeared as quickly as it had arrived.

Berdych, whose strong ground game and powerful serving had won him a growing number of casual and deeply surprised fans, plainly felt his breath tighten at the prospect of adding the greatest tremor of all to this tumultuous, hazardous Wimbledon.

At the end of the first set his nerve shredded when he drove a strangely tepid Djokovic drop shot into the net and it seemed to be an entirely similar process when he swiftly surrendered his new advantage. Later he said: "He didn't start the second set well but I just took a chance on it, and then it started going bad for me because, you know, you just cannot give him any kind of chance. I know I can play much better than I did today but if you give him anything he makes it such a lot. So what it means is that you have to be on the limit all the time, and playing really great, to have a chance to beat him."

There were moments when Berdych unleashed impressive power and gave the impression that he was indeed up for a serious fight. However, if any man is programmed to eat away at such a resolve it is Djokovic, the relentless fighter and a stroke-maker who some hard judges now believe is on the verge of breaking into uncharted ground. He won 7-6, 6-4, 6-3 in two hours, 15 minutes. In the end it wasn't so much a contest as a ritual, with Djokovic in charge of both the choreography and the key dramatic moments.

He treated the crowd as his own, people drawn into the mesmerising spell that settles over the most brilliant of his work.

It was pointed out that his duel with Del Potro, the Argentinian winner of the 2009 US Open, will be his 13th Grand Slam semi-final in a row. Did he get a special feeling when he reached the final stages of a great tournament?

"Well, it is a special task to try to reach Roger [Federer's] thirtysomething titles." There was much laughter but it hardly deflected the sense that Djokovic knows precisely how many Grand Slam titles Federer has won (17) and how long it might take him to reach the mountain top.

"I'm kidding," says Djokovic. "It is a huge achievement for me. I'm very proud of my success in Grand Slams because this is precisely what I want to do and where I want to be.

"These are the most important, most valuable tennis tournaments in the world, especially Wimbledon – so of course I feel good. I'm pleased with my consistency – and the fact that I understand better than ever what I have to do to keep my position in the game."

For some time now Djokovic's ambitions have been defined by the work he does and the quality he achieves and provided a classic example of how a great effortlessly moves on to another level when there is a hint of crisis in the air.

Murray entered a long and draining ordeal. Djokovic simply changed a gear. Can he get better? It's a frightening question, but then so is the answer. Novak Djokovic continues to wield it like a banner.

Better than ever? Djokovic SW19 stats

Novak Djokovic is yet to drop a set this year, while he is also averaging more aces than in the two previous years – including his 2011 triumph.

Sets dropped:

2011 4 (in seven matches)

2012 4 (six)

2013 0 (five)

Aces:

2011 61 (8.7 per match)

2012 53 (8.8)

2013 54 (10.8)