Shanghai, 15 October

Novak Djokovic sauntered past Spaniard Feliciano Lopez to reach the quarter-finals of the Shanghai Masters on Thursday but Andy Murray had to claw past big-serving American John Isner after losing a first-set tiebreaker.

Dominant world No 1 Djokovic, twice a champion in Shanghai, eased to a 6-2, 6-3 victory to stay on track for a ninth title of the year having picked up his eighth last week in Beijing where he dropped only 18 games in five matches. The Serb, who could face Murray in the semi-finals, looks unbeatable, but warned there is still 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,” Djokovic said.

Murray, playing his first tournament since helping Britain into the Davis Cup final last month, had to produce some of his best tennis in the face of 22 Isner aces. The 28-year-old world No 2 finally preserved his perfect record against the American, winning 6-7(4), 6-4, 6-4.

Murray managed a crucial break of serve at 5-4 in the second set and broke a tiring opponent in the seventh game of the final set on his way to victory. “His serve is tough to read, obviously,” Murray said. “He has a great serve. It’s hard to return in perfect conditions.” While Djokovic is beyond his reach in the rankings this year, Murray believes he can have a tilt at top spot next year. “Obviously this year I have a good chance to finish at No 2, which would be the first time for me,” he said.

Rafa Nadal, seeding eighth in Shanghai, continued his recent resurgence that saw him reach the Beijing final, moving through to the quarter-finals with a 6-3, 7-6(3) win over Canada’s Milos Raonic.

Japan’s Kei Nishikori was beaten 7-6(10), 7-6(3) by South Africa’s Kevin Anderson who still has his eye on a place in the ATP World Tour Finals in London. Anderson will face Frenchman Jo-Wilfried Tsonga next after he beat Roger Federer’s Spanish conqueror Albert Ramos-Vinolas 6-7(5), 7-5, 6-4.