Top seeds Juan Martin del Potro and Janko Tipsarevic boosted their chances of reaching the season-ending ATP World Tour Finals on Friday when they eased into the Austrian Open semi-finals.
Number one seed Del Potro, playing his first event in a month after a wrist injury suffered in the Davis Cup semi-finals, had too much class for Australia's Marinko Matosevic, 6-2, 6-2.
Tipsarevic, still jet-lagged from playing in Shanghai last week, enjoyed a swift 6-2, 4-2 passage after Slovenian opponent Aljaz Bedene quit with a thigh injury.
The 63-minute result was welcomed by the second seed, who had played both singles and doubles the day before.
But there was disappointment for third-seeded Tommy Haas as the German veteran went down on six breaks of serve to Grega Zemlja of Slovenia, 6-4, 4-6, 6-2, just a day after notching his 500th career win.
On Saturday, Del Potro will face Gilles Muller who beat Paolo Lorenzi 6-3, 6-4 while Tipsarevic will get a re-run of a US Open match-up when he faces Zemlja, ranked 70th.
Del Potro and Tipsarevic are chasing two of the three remaining places in the eight-man World Tour Finals which start on November 5 in London.
With this weekend, and two more weeks of play remaining, every match counts.
"I had a good match but you can always improve some things," said Del Potro. "Against Muller, I will have to try and break his big serve and hold my own.
"I'm ready for a tough match, I need more matches since I've only played two since returning this week. I need to improve for the semi-finals."
Tipsarevic stands ninth in the race to London and is doing his best to keep his mind in the present.
"I would lie if I said I was not thinking about London," said the Serb, now 55-22 this season with a title from Stuttgart.
"It is in the back of my mind. But this is an important tournament for me. I'm trying not to think too far ahead. Doing so only creates added pressure which is not helpful.
"I'm only thinking about my next match - I'm trying not to care about London right now."
Zemlja said he quickly got over pre-match nerves to reach his first ATP semi-final.
The Slovenian, who often trains in Austria, broke Haas in the fifth game of the final set to run out the winner.
"I did well, I showed that I can beat a lot of good players. In the third set I felt his forehand was getting vulnerable. I just stayed steady with my game."