By Sophie Brown
BBC Sport at Wimbledon
Novak Djokovic saw off Marcos Baghdatis in a five-hour thriller to earn a semi-final with Rafael Nadal.
Djokovic reached his first Grand Slam semi in Paris last month
Serb Djokovic, 20, took the first two sets on tie-breaks, winning the second 11-9 with his first set point after Baghdatis had missed six of his own.
Cheered on by his vocal Cypriot fans, Baghdatis won the third tie-break and came from behind to win the fourth set.
But third seed Djokovic pounced at 5-5 in the decider before serving out for a 7-6 7-6 6-7 4-6 7-5 victory.
Once Djokovic had snatched the second set and gone a break up in the third, it looked as if he was on course for a straight-sets win.
But Baghdatis then reeled off five games in a row and although he was broken serving for the set, this time he held his nerve in the tiebreak.
In the fourth set, Djokovic was again a break up but once again 22-year-old Baghdatis fought back to force a deciding set.
Games went with serve until 5-5 when Baghdatis put a simple forehand into the net to give Djokovic the chance to break.
He then calmly served out for victory but there will be no time to celebrate as the Serb, who needed treatment for a back injury during the match, will be back on court at 1100 BST on Saturday.
It was important to win quickly after two very tough games
"After what I have been through in these last two weeks - and after playing 9½ hours in two matches, I don't know how I have managed," said Djokovic.
"I'm playing the best tennis of my life but I'm pretty exhausted."
Baghdatis said: "I'm a bit disappointed. I had my chances in the first and second set. I gave everything.
"I would give Nadal a 60:40 chance (of winning the semi-final) because Djokovic will be tired."
Second seed Nadal was the first man to book his place in the last four with a straightforward win over Tomas Berdych.
After taking six days and 10 sets to negotiate his previous two rounds, the Spaniard needed only just over two hours to beat the Czech seventh seed.
On a gusty Centre Court, Nadal took the first-set tie-break and a break at the start of the second put him in charge.
The 21-year-old then raced through the final set for a 7-6 (7-1) 6-4 6-2 win.
For Berdych, also 21, it marked a sorry debut in a Grand Slam quarter-final as his game seemed to crumble after the first-set tie-break.
Meanwhile Nadal was in the unaccustomed position of being able to put his feet up while waiting for the other quarter-finals to finish.
In the last four, last year's runner-up will play either fourth seed Novak Djokovic or 10th seed Marcos Baghdatis.
Nadal said he was "very happy" to have enjoyed such a straightforward win in the windy conditions.
"It's very difficult to play with this wind but I am very happy because I played a good match. It was important to win quickly after two very tough games."
Berdych blamed the "impossible conditions" for his poor performance in the final two sets.
"I don't like these kind of conditions on the court and I think it's not good for tennis at all," he said. "They were impossible conditions."
The Czech, who also echoed other players' criticisms about not playing on the middle Sunday of the tournament, said he still felt top seed Roger Federer would be the overwhelming favourite against Nadal.
"Nadal is a great player but I think Roger is the best on the grass," said Berdych who was beaten by Federer in last year's fourth round.