Men's top seed Novak Djokovic maintained his perfect China Open record but Caroline Wozniacki's hopes of qualifying for the year-ending WTA Finals in Singapore took a hit after she crashed out.
World number one Djokovic needed 85 minutes to overcome Canadian Vasek Pospisil 6-3 7-5 in the second round and extend his China Open record to 21-0.
Djokovic, eyeing a fifth title at Beijing, broke the big-serving Pospisil four times and lost only six points on his first serve in his dominant display.
In the women section, Australian Samantha Stosur showed flashes of her old brilliance to beat Wozniacki 6-4 7-6 in their second-round encounter.
Wozniacki needed to win the Beijing title to qualify for Singapore but was troubled against a sharp-serving Stosur, who broke her in the seventh game to claim the first set and saved five set points in the tiebreak before closing it out.
Wozniacki can still qualify for Singapore this week, if Angelique Kerber does not reach the quarter-finals and Ekaterina Makarova falls before the final.
Third seed Petra Kvitova, the fourth and the latest to qualify for the eight-player season finale, beat local favourite Peng Shuai 6-4 6-2 in another second round match.