Wimbledon champion Maria Sharapova beat former winner Venus Williams, 6-3, 6-4, in the Swisscom Challenge quarterfinals on Friday and extended her winning streak to 11 matches.
Fourth-seeded Sharapova will continue her quest to win three successive titles when she meets No. 3 Elena Dementieva in an all-Russian semifinal today.
Sharapova won in Seoul and Tokyo and has dropped only one set in three tournaments.
The seventh-seeded Williams, who won the tournament in 1999, broke Sharapova in the opening game of the match. The 17-year-old broke Williams twice, however, to come back and win the first set.
In the second, Sharapova broke for 4-3 and served for the match at 5-4.
Williams had a break point but couldn't convert, and Sharapova finished with two unreturnable serves to clinch the victory in the first meeting between the players.
Dementieva, runner-up at the French Open and U.S. Open, battled past No. 9 Ai Sugiyama of Japan, 6-1, 5-7, 7-5.
No. 10 Patty Schnyder -- the 2002 champion -- defeated Argentina's Paola Suarez, 6-2, 3-6, 6-4.
In the semis, Schnyder will face Olympic bronze medalist Alicia Molik of Australia, who easily defeated No. 8 Nadia Petrova of Russia, 6-3, 6-1.