Andy Murray believes his second-round win over Somdev Devvarman at the Shenzhen Open will stand him in good stead to reach the ATP World Tour finals.

The 27-year-old faces a battle to reach the showpiece event at the O2 Arena in London as he currently stands 11th in the Race rankings with only the top eight sure to qualify.

With every point counting, Murray accepted a wild-card to compete in China and sailed into the quarter-finals in his first match since his US Open quarter-final defeat to Novak Djokovic. Murray broke twice in the first set without reply and, despite being broken in the second, he converted both of his own break- point opportunities to move through 6-3, 6-3 in one hour and 21 minutes.

"I thought I did pretty well," said the Scot. He [Devvarman] makes very few mistakes - he's a solid player and he moves well. It was very humid out there. It was good to have a tough workout like that."

In the quarter-finals Murray will play the Slovakian world No.85 Lukas Lacko, who beat Ricardas Berankis of Lithuania 6-4, 7-6 (7-1).

Top seed David Ferrer was bundled out by Serb Viktor Troicki 6-3, 6-4 which will not help his chances of reaching the ATP World Tour finals. Ferrer, 32, is currently seventh in the race to qualify with Novak Djokovic, Roger Federer and Rafa Nadal already having booked three of the eight spots for the singles.

Tomas Berdych is almost neck and neck with Ferrer, just 25 points behind in eighth spot before this week's tournaments, but ninth-placed Milos Raonic is not far behind, with Grigor Dimitrov and Murray on his heels.

World No.174 Troicki fired 13 aces to canter to victory in just 66 minutes, his first over world No.5 Ferrer in four matches.

Wimbledon champion Petra Kvitova ended the dream run of France's Caroline Garcia with a clinical performance to reach the semi-finals of teh women's event.

Kvitova, the highest seed standing at the hard court tournament after the exits of top two seeds Serena Williams and Romanian Simona Halep, defeated Garcia 6-3, 6-4. The 24-year-old Czech broke Garcia, ranked 49 in the world, once in each set to win the quarter-final.

Garcia, 20, accounted for former world No.1 Venus Williams and Agnieszka Radwanska en route to the last eight but too many unforced errors hurt her yesterday.

The victory also kept Kvitova on course for qualifying for the year-ending WTA Finals in Singapore.