LONDON, July 3 (Reuters) - Andy Murray's predicted stroll to the Wimbledon final became a hazardous obstacle course on Wednesday as he was forced to claw back a two-set deficit against Fernando Verdasco to join top seed Novak Djokovic in the last four.
The imperious Djokovic, the man Murray is expected to face in Sunday's final, swept past Czech Tomas Berdych 7-6(5) 6-4 6-3 to reach his 13th successive grand slam semi-final without dropping set.
Murray prevailed 4-6 3-6 6-1 6-4 7-5 to reach his fifth successive Wimbledon semi-final but will require soothing balm on his nerves, and some more for his army of fans, before taking on the 140mph serve of Jerzy Janowicz, Poland's first male grand slam semi-finalist, on Friday.
Towering Argentine Juan Martin del Potro may need extra bandages for his battered left knee after a horrible tumble during fifth point of his quarter-final against David Ferrer looked like dealing him a cruel knockout blow.
The 24-year-old climbed off the deck, however, to pummel the Spanish fourth seed 6-2 6-4 7-6(5) with a performance reminiscent of those that took him to the 2009 U.S. Open title.
Janowicz, a qualifier last year who has rocketed up the rankings, beat fellow Pole Lukasz Kubot 7-5 6-4 6-4 in an unlikely quarter-final that, had the tournament gone to plan, would have been between Roger Federer and Rafa Nadal.
The youngest of the eight quarter-finalist will now set his sights on Murray, hoping to wreck the second seed's hopes of becoming Britain's first men's Wimbledon champion since Fred Perry in 1936.
"Right now I'm the most happy person in the world," said the 22-year-old Janowicz, who launched 30 aces past Kubot to surpass the feat of compatriot Wojtek Fibak who lost four grand slam quarter-finals.
"I hope Andy will feel some kind of pressure. I'm sure he will feel some kind of pressure because Britain is waiting for the English champion in Wimbledon."
Murray, who is actually Scottish, is used to handling the pressure of being his country's only realistic grand slam hope and delivered a U.S. Open title last year after losing his first Wimbledon final to Federer.
When the draw opened up after a first week of shocks and injuries, Murray's path to the final looked an enticing one.
But things are rarely that simple.
There were a few wobbles against Mikhail Youzhny in the fourth round and he endured a full-blown crisis against unseeded Spanish left-hander Verdasco who blazed away with his serve and forehand to move two sets ahead.
Murray won the third with ease but twice had to fend off break points in the fourth before levelling the match in an electrifying atmosphere on Centre Court.
Verdasco refused to cave in, however, and a nail-shredding deciding set went with serve until Murray broke through at 5-5 and kept a cool head to serve out to love and spark wild celebrations around the grounds.
It was the seventh time in his career Murray has recovered from two sets down to win a match.
"I think I've learnt how to come back from tough situations more as I got older," said the 26-year-old who was watched by former Manchester United manager and fellow Scot Alex Ferguson.
"It's a great atmosphere to be playing in. I love it when it's like that. It was extremely noisy."
Six-times grand slam champion Djokovic had the tougher task on paper against the hard-hitting Berdych who had won their only previous match at Wimbledon.
He edged a high-quality first set but fell 3-0 behind in the second before finding the extra gear that so often comes to his rescue when faced with danger.
"It was toe-to-toe in the first set and one shot decided the first set," the 2011 champions said. "Even though I started poorly in the second, I still felt quite good on the court. Just really glad to go through in three."
Del Potro's medical team will be working overtime in the next 24 hours, especially as the eighth seed said he needs to be at 110 percent to have a chance against Djokovic.
"I'm not going to put my body at risk," he told reporters. "The doctors tell me with this tape and taking some anti-inflammatories you can play.
"If they say something different, I will think."
Del Potro looked down and out when his already-bandaged left knee crumpled as he tumbled chasing a wide ball.
Grimacing in pain the six foot six Argentine climbed up from the turf and after treatment and a pain-killing tablet unfurled his right arm to its full condor-like wingspan and began to pound French Open runner-up Ferrer into submission.
Such was the venom in his murderous forehand that any injury concerns were put aside as he struck 22 winners on that flank alone, including a screamer on match point.
"I was very close (to pulling out) because I felt a lot of pain in the beginning of the match. I twisted my knee once again and the doctor gave me some magic pills and I could finish the match," said Del Potro.
"I tried to be positive and played unbelievable tennis."
(Editing by Ed Osmond)