Defending champion Dmitry Tursunov will play former champion James Blake in the semi-finals of the Indianapolis Championships.
Blake, who is seeking his second title here in three years, is the top seed for the tournament and progressed thanks to a 6-2 6-0 victory over unseeded Yen-Hsun Lu of Taiwan.
He will face third seed Tursunov who beat Paul Capdeville of Chile 3-6 6-3 6-1.
Looking forward to the challenge, Blake said: "Tursunov is a great player and ... he's a guy that can give you a hard time.
"I know he's got a lot of firepower."
In the other semi-final, fourth seed Sam Querrey will play second seed Gilles Simon of France.
It is the first time that all four top seeds have advanced to the semis since the tournament moved to a hard-court surface in 1988.
Speaking of that, Blake added: "That's strange these days in tennis - top seeds get upset all the time.
"It's really not easy to go through and beat every guy you're expected to beat. You know anyone can beat you on a given day."
Querrey advanced to the semis thanks to a hard-fought 6-1 3-6 6-3 victory over fellow American Bobby Reynolds.
He said: "I might have gotten a little content or lazy or something and he picked it up in the second set.
"After he got up a break in the third, I got it back together. I put some returns in the court and started picking up my game a little."
Simon beat fifth-seeded Tommy Haas of Germany for the first time with a hard fought 4-6 6-4, 6-2 victory.
He put his victory down to being more aggressive and hitting the ball harder in the final two sets.
He added: "When you play Tommy, the hardest thing is to return. He has a second serve that is hard to read and you don't know where it's coming."

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