Berdych says umpire was scared of Nadal

Rafael Nadal roared into the semi-finals of the ATP World Tour Finals in London on Friday with a 7-6, 6-1 defeat of Czech Tomas Berdych who later accused the Spaniard of intimidating the umpire.

A sensational first set boiled over in the 12th game when world number one Nadal became involved in a heated debate with Brazilian chair official Carlos Bernardes after a controversial Hawkeye challenge.

With Berdych fighting to stay alive in the eight-man event, he challenged an overrule at 15-15 on Nadal's serve and the resulting Hawkeye review shown on the O2 Arena's huge screens confirmed his backhand had clipped the baseline.

Bernardes awarded the crucial point to Berdych even though Nadal said he had stopped playing when he heard the umpire incorrectly call the Czech's backhand out.

Nadal was enraged and even walked off the court behind the umpire's chair to talk to the tournament supervisor Tom Barnes before eventually returning to the court and holding serve.

"It just shows how the referee is probably scared of him and just let him talk with him too long," world number six Berdych, whose chances of reaching the semis on his debut at the tournament vanished, told reporters.

"I was waiting while he was talking for like three minutes. He was like sitting there and he's not going to play, stuff like that. It's not the mistake of Rafa. It's the mistake of the referee. He just needed to show him that it's not like he can do whatever he wants on the court."

Nadal was clearly still furious and took his frustration out on the unfortunate Berdych whose level dropped significantly in the tiebreak which he lost 7-3.

CLIPPED BASELINE

Afterwards Nadal offered a slightly different version of events, refuting Berdych's suggestion that he had raised his arm during the point indicating he wanted to challenge the Czech's backhand which was later shown to have clipped the baseline.

"I didn't challenge," Nadal, who will play Britain's Andy Murray on Saturday, told reporters. "(The umpire) called the ball out. Maybe I stopped a little bit because the ball was really close. To stop the point you have to say stop."

Nadal said the incident may have affected Berdych.

"This point doesn't change a lot (for me), " he said. "Finally I was lucky. I won that game. I think I was still playing the same level before that point and after that point.

"But maybe Tomas goes down a little bit in the second set and I was feeling better and better."

Nadal's win meant he remained undefeated in Group A and he is now just two wins from claiming his first title at the year-ender and a $1.6 million jackpot.

However, he warned that facing Murray would be tough.

"If you talk to the specialists of tennis, everybody can say the conditions are a little bit easier for Andy than for me here," the nine-times Grand Slam champion said.

"The court is a little bit easier for him than for me. But the only thing that really matters is what happens tomorrow."

Nadal beat Murray in the Wimbledon semi-finals this year and holds an 8-4 career lead over the Scot although he did lose when they last played in Toronto this year.