World number one Novak Djokovic survived an energy-sapping streetfight with David Ferrer and Andy Murray cut Kei Nishikori down to size to reach the Australian Open semifinals on Wednesday.
Defending champion Djokovic appeared to tweak a hamstring early in the second set as he lunged along the baseline but ground out a 6-4, 7-6, 6-1 win in two hours, 44 minutes.Briton Murray had a far less taxing time against Japanese Nishikori, who was walking tall after a shock win over world number six Jo-Wilfried Tsonga in the fourth round.
Murray dominated Nishikori despite struggling on serve, pounding out a 6-3, 6-3, 6-1 win to set up a semi-final clash with Djokovic.
Serb Djokovic has been in majestic form since his Australian Open win kickstarted a stellar 2011 season but it was heart and lungs that got him past Ferrer.
The 24-year-old was bent double, gasping for breath early in the first set as the terrier-like Spaniard dragged him to the four corners of the court in a succession of lung-bursting rallies.
Ferrer doggedly chased down everything thrown at him but was powerless to stop Djokovic's charge to victory as the Serbian found his range with blistering backhands and mixed in some deft dropshots to keep the fifth seed guessing.
"David makes you run, makes you play an extra shot, makes you earn your points," Djokovic said.
"In these conditions, at this stage of the tournament when you're playing somebody like David, somebody that has great shots from both sides from the baseline, makes you always play over five to 10 shots in the rally, your physical strength and endurance comes into question."
Murray's coach Ivan Lendl was on hand to check out the Scot's semi-final opponent and will have been rubbing his hands with glee watching Djokovic being pushed to the limit.
Murray was never in any danger of succumbing to another seismic shock at Melbourne Park against Nishikori, who had ousted Frenchman Tsonga to become the first Japanese man through to the last eight in Melbourne for 80 years.
Cheered on by kimono-clad fans, 24th seed Nishikori did not hang around long enough to be a pain in Murray's neck and the Japanese bowed out with barely a whimper.
"I had a sore neck today when I woke up and I wasn't feeling all my serve. I don't know if it had anything to do with that," the 24-year-old Briton told reporters.
"It's good to see that I've been playing my best tennis at the slams because that's something the last couple years I wanted to make sure I was doing. That wasn't always the case."
Top four too good
The top four seeds-- Djokovic, Murray, Rafael Nadal and Roger Federer-- thus will once again headline the semis of a Slam
Speaking after his loss to Djokovic, Ferrer said, "I think the top four players are better than the other ones. I don't think (the gap can be closed). Last year, the top four players played all the finals (at) the Grand Slams and this year they are doing again. I think the top four is another level."
Djokovic agreed, saying: ""We have this mental strength and advantage."