Radwanska knocked out by Serena; Zheng gains victory over teenager Vaidisova

The Williams sisters could be the ones to battle it out in the final, as they won their matches with ease, while their future semifinal opponents won their matches with need of very hard work.

Venus Williams, seeded No. 7 and going for her fifth Wimbledon title, was the first to reach the semifinals, beating breakthrough story Tamarine Tanasugarn in straight sets, 64 63. Venus hit 22 unforced errors and gave Tanasugarn 10 break chances, with Tanasugarn winning only one break point.

"I think the key in this tournament has been my serve; any time I'm down break point or double break point, my serve gets me out of it," Williams said. "I expect that from myself. I expect when times are tough to really get going. That has been the basis of my game for a long time. On those break points you've got to play better, so I'm blessed to have a serve to get me out of those issues."

"I tried the best I could today," Tanasugarn said. "I had so many break points in the first set, but top players like Venus don't give you any easy chances, so you have to make it. And she served really well during the break points. She has some very big weapons on this surface. And she wasn't falling apart; she didn't give me any chances to come back in the match. So it was very difficult."

Tanasugarn had a brilliant grass court season, winning her first tournament on the surface at 's-Hertogenbosch, on the way winning to Top 10 players Jelena Jankovic and Dinara Safina, and now being the first Thai woman to be in a Grand Slam quarterfinal.

"Obviously she was playing well to get to the quarterfinals," said Williams on Tanasugarn. "Her game is really suited for the grass; her shots are really, really low to the ground. I was battling just to stay down on the shots. I felt good when I got one up in my strike zone. Maybe I had a little more in my game than the players she played before, and that helped me get through it."

Next to face Venus Williams is Elena Dementieva, who was trying hard to get victory over countrywoman Nadia Petrova in three sets, 61 67(6) 63. Dementieva led 61 51, but Petrova came back to make it equal at 5-5, and then took the set to a tiebreak which she won, fighting back from two match points down at 6-4.

"It feels wonderful," Dementieva said. "It's my first semifinal here and I'm very excited about it. As anyone could see, I was really, really tight. In the second set I had the feeling of almost being in the semifinals and lost my concentration. It was really difficult to start all over again in the third. But I'm just really happy I was able to get through such a difficult situation in my match and finish well."

"This match was a big opportunity and I missed it," said Petrova, who was hoping to reach her third Grand Slam semifinal, having done so twice before at Roland Garros. "It has been a good run for me. I'm happy I'm getting my game back. I'm going through all the match situations again, all the play, all the emotions. So, it's like doing it all the way from the beginning."

Serena demolishes Radwanska; Zheng stuns Vaidisova

Serena Williams, seeded No. 6,younger sister of Venus, and going for her third Wimbledon title, dominated the court against Agnieszka Radwanska with an easy 64 60 win. Williams had five times more winners than unforced errors, firing aces, forehand and backhand winners from everywhere around the court.

"I definitely felt I stepped it up a notch, mostly with my serve," Williams said. "I expected Radwanska to get a lot of balls back, like she did, and make some good shots, like she did. She always hits an extra ball, like I had to do out there."

Radwanska came into Wimbledon from a warm-up tournament, Eastbourne, winning the title and getting past top players like Marion Bartoli in the semifinals and Nadia Petrova in the final.

Next to face Williams is wildcard Jie Zheng, who gained victory over teenager Nicole Vaidisova in a three-setter, 62 57 61. Zheng, who beat top seed Ana Ivanovic on the way to the semis, became China's first ever Grand Slam semifinalist, beating Li Na's record here two year ago, when she finished her run in the quarterfinals.

"I've been watching her play; I think she's doing a fabulous job, and I don't think it's luck, her doing so well," Williams said on Zheng. "I think she's a really good player. I'm definitely not going to underestimate her. I'm going to try to fight and do the best that I can do."