Novak Djokovic improved his perfect record at the China Open to 25-0 by beating Simone Bolelli of Italy 6-1, 6-1 in the first round.
The top-seeded Djokovic's winning streak started in 2009, when he won the first of his five titles at the tournament. He has dropped only three sets out of 51 in his five appearances. He did not play in 2011.
Besides singles, Djokovic is also teaming with younger brother Djordje in doubles for the first time at an ATP Tour event.
Rafael Nadal also advanced to the second round, beating Chinese wild-card entry Wu Di 6-4, 6-4.
Nadal dropped serve four times in the match, including three straight games in the second set.
The third-seeded Nadal is in the uncharacteristic position of needing a strong finish to the season to qualify for the ATP Finals in London next month.
"I think I played little bit too ... far away from the baseline," Nadal said. "The last three games of the match I was playing better. I hit some good forehands down the line and that's why I finished well."
In the women's draw, US Open champion Flavia Pennetta of Italy rallied to advance to the third round with a 3-6, 6-0, 6-4 win over Teliana Pereira of Brazil.
Also, eighth-seeded Caroline Wozniacki of Denmark defeated Chinese wild-card entry Wang Qiang 7-5, 6-0, and 10th-seeded Angelique Kerber of Germany beat Dominika Cibulkova of Slovakia 6-1, 6-4.
John Millman (Australia) beat Tommy Robredo (Spain) 4-6 6-1 6-0
1-Novak Djokovic (Serbia) beat Simone Bolelli (Italy) 6-1 6-1
3-Rafa Nadal (Spain) beat Wu Di (China) 6-4 6-4
Vasek Pospisil (Canada) beat Victor Estrella (Dominican Republic) 4-6 7-5 6-0
Lu Yen-Hsun (Taiwan) beat Adrian Mannarino (France) 6-3 6-2
10-Angelique Kerber (Germany) beat Dominika Cibulkova (Slovakia) 6-1 6-4
Sara Errani (Italy) beat Caroline Garcia (France) 6-4 3-6 6-1
3-Flavia Pennetta (Italy) beat Teliana Pereira (Brazil) 3-6 6-0 6-4
Bethanie Mattek-Sands (U.S.) beat Lara Arruabarrena Vecino (Spain) 0-6 6-2 6-0
8-Caroline Wozniacki (Denmark) beat Wang Qiang (China) 7-5 6-0