New shoes please...Djokovic is slipping at the All England club

Top seed Novak Djokovic slipped and slid his way into the Wimbledon semi-finals on Wednesday, overcoming Marin Cilic and the distractions of Henman Hill to win 6-1, 3-6, 6-7(4), 6-2, 6-2 with the help of a new pair of shoes.

The Serbian former champion began efficiently against the lofty Croat, rattling through the first set in 27 minutes on a sunny but subdued Court One.

The crowd had half an ear outside Court One where spectators watching the big screen on the hill whooped and groaned through champion Andy Murray's defeat by 11th seed Grigor Dimitrov.

Djokovic's intensity dropped in the second set. The world No.2 lost his footing several times in the baseline dust and his Croatian opponent grabbed a break of serve in the fourth game using his big forehand to pummel the six-times grand slam champion.

"We could hear the crowd during the match and it was a bit distracting; but no excuses, we had to concentrate," Djokovic said.

"I said to the chair umpire, Let's just stop the match, put it live on the big screen, and let's watch it till they're done. It's going to be better for all of us."

The pair fought a tight third set, watched by their celebrity coaches, former champions Boris Becker and Goran Ivanisevic from the player's box.

Djokovic hit the ground three times during the tiebreak, on one occasion tumbling spectacularly into the net.

"It was a tough five-setter. Coming in I knew Marin would play aggressively," he said.

"He raised his game but I allowed him to come back into it. I was too passive on my strokes and he used his opportunities, but I managed to find the right pace when I needed it."

Djokovic donned a new pair of shoes early in the fourth set, upped the pace and raced into his 23rd semi-final, where he will meet 23-year-old Bulgarian Dimitrov.

"After I changed my shoes I played well," a smiling Djokovic said.

"I had just a better grip. I had better movement. Maybe it was just mental, but anyway, it worked."

He added he would keep the lucky shoes to play Dimitrov.

"It was a big win for Grigor. He's on fire this last six months," Djokovic said.

"The fact that he hasn't lost a match in the grass court season this year says enough about his quality.

"Also winning against Andy. I'm sure many people look at him as a potential grand slam winner. Maybe here, maybe in the grand slams to follow."