Andy Murray, David Ferrer Hot Up Race to London With Quarterfinal Wins in Vienna

Andy Murray and David Ferrer tightened the duel for spots in the ATP year-end final with a pair of wins into the semifinals of the Austrian Open on Friday.

Murray, seeded second and the heavy crowd favourite in his debut at Vienna's Stadthalle, played it safe against German Jan-Lennard Struff in a 6-2, 7-5 win.

Spain's top seed Ferrer limited the damage from the lethal serve of Ivo Karlovic as he defeated the sixth-seeded Croatian 7-6 (7/5), 6-4, holding Karlovic to 17 aces.

Ferrer won the first set in 44 minutes from two unforced Karlovic errors and secured a break in the seocnd set for what proved to be a winning margin. He has now won three of four matches in the series,

Ferrer stands provisional ninth in the race for one of three remaining places at the World Tour Finals, one spot ahead of Murray.

Murray will Saturday face Viktor Troicki, who took a big step in his return from tennis exile as he beat Thomaz Bellucci 7-6 (7/4), 6-7 (2/7), 6-2 to reach his first semi-final since 2011.

Ferrer will take on fourth seed Philipp Kohlschreiber, a winner over Benjamin Becker 6-4, 7-6 (7/3).

Murray's only wobble against the 52nd-ranked Struff came as the Scot trailed 3-1 in the second set, but

Murray quickly put that right and returned to 3-all. The former Wimbledon champion ran out the winner after less than 90 minutes with a love game.

"I expected a tough match from him, even if I didn't know a lot about his game," said Murray, provisional tenth in the race to London which will be decided this weekend and over the remaining two weeks of the ATP season.

"He was hitting big. I had to play well to win and fight to get through. My game was more consistent than in the previous round, I was able to change up the rhythm

"He was playing high-risk tennis but he made a couple of mistakes which helped me. I still was not able to hit a lot of winners."

Number 127 Troicki has crawled back up the rankings after returning in July from a one-year ban for delaying a post-match blood test in 2013.

The 28-year-old made his return with just 20 ranking points remaining thanks to a wild card from Gstaad organisers.

He reached the quarterfinals in Switzerland and did the same last month in Shenzhen, China.

A Beijing wild card produced a first-round win, with Troicki capitalising on success from qualifying to carve his way through the Vienna event upon his debut.

The Serb last played a semifinal at Moscow, 2011. "It's great to win," said the player who was stoutly defended during his ban by world number one and good friend Novak Djokovic.

"I've not played a semifinal in a long time. "My comeback has been tough but I always knew it would be like this: you have to come from the bottom if you want to arrive at the top."

Troicki said that while he tries to bury bitter memories of the sanction he received after being informed - erroneously as it turned out - that he could postpone a blood test by 24 hours due to feeling poorly in April, 2013, in Monte Carlo, the episode remains distasteful to him.

"That you didn't do anything wrong and you are being punished is the worst feeling," he said. "One year is a long time in any sport.

"They told me at the tribunal hearing that if I had just taken something illegal in my body I would have gotten a lesser sentence. As it turned out, 12 months was the minimum punishment for missing a test.

"And the International Tennis Federation lawyers were trying to get me banned for two years.

"But it's over now. Inside myself I know I was clean and not trying to do anything wrong. I had good lawyers but you feel like you don't have any chances (in the hearing)."