Djokovic charges into Shanghai quarters

Tennis World No.1 Novak Djokovic remained on track for his ninth title of the season after a dominant 6-2, 6-3 win against Spaniard Feliciano Lopez at the Shanghai Masters here on Thursday.

The Serbian clinched his seventh victory in as many meetings against the left-handed 15th seed to move through to the quarter-finals.

It was his 70th match win of the year. Djokovic's 22-17 winners to unforced errors ratio proved telling against Lopez's 13-28.

It extended his winning record on Chinese soil to 35-1 after claiming the title in Beijing last week. Despite being in some of the best form of his career, he said there was still room for improvements while striving to maintain his current level.

"I think it's a combination of the two - maintaining the high level, the performance, the tennis I have right now, and also working on certain parts of the game that I think can be improved," Djokovic said after the match.

"I was brought up that way and thought to always look for some room for improvement. I still believe there are shots in my game that can be better. I think that's one of the things that keeps me going. It motivates me to play more."

South African Kevin Anderson reached the quarter-final with 7-6 (10), 7-6 (3) win against No.3 seed Japanese Kei Nishikori on Thursday.