Top seed Rainer Schuettler cruised into the quarter-finals of the $860,000 Japan Open with a clinical 6-3, 6-2 victory over American Robert Kendrick on Thursday.
The German was too sharp with his returns and too quick around the court for Kendrick in a one-sided match.
He finally put his error-prone opponent out of his misery with a well-placed overhead smash after just 64 minutes.
Schuettler, sixth in the ATP Champions Race and aiming for a spot in the season-ending Tennis Masters Cup for the first time, will play Scott Draper next after the Australian upset German sixth-seeded Nicolas Kiefer 7-5, 6-2.
"Every point is important for me because if the other players play well they can kick me out of the Masters Cup," said Australian Open runner-up Schuettler.
"When I was growing up I always watched the Masters Cup on TV as a kid and I definitely want to be part of it this year."
Third-seeded Paradorn Srichaphan, still with an outside chance of qualifying for the prestigious eight-man tournament in Houston from November 8-16, beat Japanese wildcard Takao Suzuki 6-2, 7-6 to reach the last eight in Tokyo.
The 24-year-old Thai plays South Korean Lee Hyung-taik in the quarter-finals on Friday after the seventh seed overpowered defending champion Kenneth Carlsen of Denmark 6-3, 6-4.
LATE BID
Fifth seed Mark Philippoussis pummelled Croatian Mario Ancic 6-4, 7-5 under floodlights to reach the last eight.
The big-serving Australian has launched a late bid to qualify for Houston after breaking a two-year title drought with victory in Shanghai last weekend.
"Obviously [the Masters Cup] is a goal but to be honest it's not my main focus," said the Wimbledon runner-up, whose career has been plagued by injuries.
"For the first time in four years I feel fresh...not stressed-out. I'm still hungry and if I keep winning matches and tournaments that's going to come."
Philippoussis, will play Frenchman Cyril Saulnier next in a repeat of their second-round meeting at Wimbledon, won in straight sets by the Australian.
Among the women, Japanese top seed Ai Sugiyama bowed out with a finger injury while trailing 6-4, 3-2 to Hungarian Aniko Kapros in their quarter-final.
Spaniard Arantxa Parra continued her dream run on her Japan Open debut, setting up a semi-final against Kapros with a 3-6, 6-4, 6-2 win over defending champion Jill Craybas.