Tokyo - French second seed Gael Monfils advanced to the Japan Open quarter-finals with a victory over compatriot Gilles Simon on Thursday in a field blighted by injury.
The world number eight nailed seven aces to oust Simon 6-1, 6-4 in one hour and 16 minutes.
The triumph was 30-year-old Monfils' second victory against Simon, ranked 30th in the world, in their eight ATP meetings.
Monfils, who has made it to the semi-final in the US Open but fell to Novak Djokovic, was a runner-up at the Japan Open's 2010 edition, when Rafael Nadal triumphed.
In the quarter-finals Friday, the Frenchman will face Croatian seventh seed Ivo Karlovic (CRO), who tiptoed past Serb Janko Tipsarevic 7-6 (11/9), 7-6 (7/5).
Gilles Muller of Luxembourg beat Marcos Baghdatis of Cyprus 6-3, 6-4, and will be pitted against Australian Nick Kyrgios, who received a pass after Radek Stepanek of the Czech Republic retired due to a back problem.
The tournament has seen major players pull out through injury.
Defending champion and US Open winner Stan Wawrinka did not take part in the Tokyo event over back trouble, while local favourite Kei Nishikori, winner in 2014 and 2012, could not finish his second-round match Wednesday because of muscle strain.
He now plans to skip next week's Shanghai Masters, but is slated to return to the court at the Swiss Indoors Basel meet later this month.
Eight seed Feliciano Lopez of Spain retired with injury on Tuesday.
Injuries also forced Argentina's Juan Martin Del Potro, Japan Open winner in 2013, to skip the tournament after receiving an invitation to join as a wildcard.
Results of second round matches at the Japan Open men's tournament in Tokyo on Thursday (x denotes seeding):
Nick Kyrgios (AUS x6) bt Radek Stepanek (CZE) retired
Gilles Muller (LUX) bt Marcos Baghdatis (CYP) 6-3, 6-4
Gael Monfils (FRA x2) bt Gilles Simon (FRA) 6-1, 6-4
Ivo Karlovic (CRO x7) bt Janko Tipsarevic (SRB) 7-6 (11/9), 7-6 (7/5)