Dinara Safina continued to make her case for the world's No.1 ranking as she reached the semi-finals of the US Open for the first time in her career.
The sixth-seeded Russian made short work of 16th-seeded Flavia Pennetta in the quarter-finals, downing the Italian 6-2 6-3 in 71 minutes.
Since starting the year 11-10, Safina has won three titles, gone 37-4 and has reached the final in six of seven events played.
If the 22-year-old can win the first grand slam title of her career at this hardcourt major, she could climb to No.1 in the world rankings, joining older brother Marat Safin, who was the No.1 player in men's tennis earlier in the decade.
"It's great," Safina said. "I'm getting closer to reaching the same thing as my brother (the 2000 US Open champion), so I hope that one day we can have the same titles."
But a difficult task is looming in the semi-finals, where Safina will have to face the winner of the match between Serena Williams and Venus Williams, who will renew their sibling rivalry later on Wednesday (US time).
"I don't care (which Williams sister I have to play)," Safina said. "Whoever shows up, I will play them."
Safina, who reached her first grand slam final at the French Open, improved to 5-0 in career meetings against Pennetta, who was appearing in her first major quarter-final.
"I don't think I played badly," Pennetta said. "I didn't make many errors (eight). I just couldn't get into the court because she kept hitting so hard."
The much-anticipated meeting between the Williams sisters comes earlier than some tennis fans would have hoped.
Venus won the most recent battle between the pair as she defeated Serena in the Wimbledon final in July. Some anticipated another championship showdown here, but those hopes were dashed when the American stars were placed in the same quarter of the draw.
Seeded fourth and seventh respectively, Serena and Venus have split their 16 career meetings. Prior to this year, they had not played each other since 2005, but this will mark their third match of 2008.
Serena won the first meeting of the season in the Bangalore semi-finals before Venus bounced back to even things en route to claiming her fifth Wimbledon title.
The pair also took the court together last month at the Beijing Olympics, teaming to take home the gold medal in doubles competition.
The Williams sisters are the only former US Open champions remaining in the field and, with 15 grand slam titles between them, there's no doubt that they are the most experienced players left.
Serena, 26, won the title here in 1999 and 2002, and if she emerges with the championship again this year she'll become the world No.1 for the first time since her 57-week reign from 2002-03.
Venus had gone 14-7 this season and was without a title prior to her breakthrough at Wimbledon. She is hoping to ride the momentum of that triumph to her third US Open title.
The semi-final on the opposite side of the draw was decided on Tuesday as No.1 seed Jelena Jankovic and fifth seed Elena Dementieva moved into the final four.
Jankovic will have to lose that match for Safina to have a shot at the top ranking, currently occupied by Serbia's Ana Ivanovic.