The sixth-seeded Venus dominated the first set at the Aviation Club as Serena struggled with her serves.
“I loved the way the first set went,” said Venus, who will face Virginie Razzano of France in Saturday’s final. “I just had two second serves in the whole of the first set.”
Venus now leads the career series between the American sisters 10-9.
“I think my serve has gone somewhere on vacation and I need to go there and catch up with it,” said Serena, the Australian Open champion. “Venus played well, and served really well, which was the difference,”
Venus hit her first ace in the second game of the second set to save a break point, and then hit another to make it 1-1 before breaking her sister twice.
“She fought back well after that, and I was still trying to finish the points quickly in the second set,” Venus said. “But when I saw that she was playing better, I had to change my game a bit.”
The sisters traded breaks in the third set.
“I was pleased with the win, but I would have been more pleased if it was the final,” Venus said. “It definitely was a final-quality match. After all, she is the No. 1 player in the world and we are the best players in the world. She is one player I respect most on the tour, so it feels very satisfying.”
Serena appeared to be bothered by a lingering knee injury that forced her to pull out of last week’s Open GDF Suez semifinals.
“I am looking forward to a break before I play Miami,” Serena said. “I really need it and I think it will be good for my knee. I have never played so much tennis in my whole career.”
Razzano beat 16th-seeded Kaia Kanepi of Estonia 6-1, 6-2. The 58th-ranked Frenchwoman had already upset second-seeded Dinara Safina and fifth-seeded Vera Zvonareva in Dubai.
Venus stuns Serena, reaches Dubai finals
Serena to meet big sis Venus in Dubai semifinals
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