( CNN ) -- Last week 's Thailand Open champion Guillermo Garcia-Lopez continued his fine run of recent form by reaching the quarterfinals of the Japan Open in Tokyo on Wednesday . The world number 39 , who beat Rafael Nadal in the Thailand semifinals last week , saw off another Spaniard -- sixth seed Feliciano Lopez -- 7-6 6-4 to move into the last eight . Czech Radek Stepanek is also through to the quarters after Swiss opponent Marco Chiudinelli retired due to a lower back injury . Stepanek was leading 5-7 7-6 4-1 and had hit 12 aces after two hours and 24 minutes of action . Meanwhile , Russian Dmitry Tursunov defeated 2007 runner-up Richard Gasquet 7-6 1-6 6-4 in two hours and four minutes reach his first ATP Tour quarterfinal since July 2009 at Indianapolis . Tursunov will now play either world number one Nadal or Milos Raonic of Canada for a semifinal place . Elsewhere , recent Metz Open winner Gilles Simon has reached the last eight of the China Open after fighting back to beat German qualifier Michael Berrer , the conqueror of Tomas Berdych in the first round , in three tough sets . The Frenchman scraped through 6-7 6-4 7-6 in three hours and seven minutes , with the help of 16 aces . American John Isner is also through to the quarterfinals after winning a big-serving encounter against Philipp Kohlschreiber of Germany 7-6 3-6 6-3 . Russian fourth seed Nikolay Davydenko continued his progress with a 7-5 7-5 success over Marin Cilic of Croatia , while top seed Novak Djokovic was handed a bye into the last eight when opponent Mardy Fish was forced to withdraw with an injury to his left ankle .
Thailand Open champion Guillermo Garcia - Lopez continues his fine run of form . He sees off saw off sixth seed Marc Lopez 7 - 6 6 - 4 to move into the last eight . Czech Radek Stepanek and Russian Dmitry Putin also through to the last 16 .