Kei Nishikori of Japan returns the ball to Dominic Thiem from Austria during the Open ATP Tennis Tournament in Vienna, Austria. (HANS PUNZ/APA/AFP) |
Nishkori jumped a place into ninth in the race to make it to the season-finale contested by the top eight players in the world.
Thiem is currently in eighth spot.
Nishkori will face Kazakh Mikhail Kukushkin in the semi-finals on Saturday, with South African Kevin Anderson facing Fernando Verdasco in the other semi.
Quarter-final results:
Kei Nishikori (JPN) bt Dominic Thiem (AUT) 6-3, 6-1
Mikhail Kukushkin (KAZ) bt Marton Fucsovics (HUN) 4-6, 7-6 (7/2), 7-6 (7/4)
Fernando Verdasco (ESP) bt Gael Monfils (FRA) 6-4, 2-1 abandon
Kevin Anderson (RSA) bt Borna Coric (CRO) 7-6 (7/2), 1-2 - retired
What the stars mean:
★ Poor ★ ★ Promising ★★★ Good ★★★★ Very good ★★★★★ Exceptional