Tipsarevic beats Gulbis

Second seed Janko Tipsarevic reached the Austrian Open quarter-finals on Thursday with a 6-3, 6-4 defeat of Ernests Gulbis and tried to put the race for the year-ending ATP World Tour Finals out of his mind. The Serb, who has been a top 10 regular for a year, said that standing provisional ninth in the chase for the eight-man London showpiece means that he must focus constantly on the court. \"I try not to think of anything before me or behind me,\" he said of the race in which he has a 400-point cushion against a pack of trailing rivals. \"I cannot be affected by the fact that everyone is chasing me. All I can do is stay completely focussed on every point of every match. I cannot think about being ahead or behind.\" Tipsarevic admitted he was worried about potential damage from Latvia\'s Gulbis, a streaky player who once stood 21st in the world before falling to his current spot of 159. \"I\'ve lost to him before, so I know how dangerous Ernests can be. But I came out on fire today from the start,\" said the Serb. \"I knew I\'d have to fight so I was aggressive from the start. I\'m very glad to win in straight sets.\" German third seed Tommy Haas was later trying to make personal history by winning his 500th career match, taking on American Jesse Levine in the second round. Haas, 34, would join an elite group of active players comprising Roger Federer (871 wins), Rafael Nadal (583) and Lleyton Hewitt on 566. The all-time leader is Jimmy Connors (1,243 wins) followed by Ivan Lendl (1,071), Guillermo Vilas (923) and John McEnroe (875). Meanwhile, Australia\'s Marinko Matosevic knocked out the last home player when he defeated Dominic Thiem 6-3, 7-6 (7/5) to set up a quarter-final with top seed Juan Martin del Potro. Matosevic, ranked 55 in the world, will be playing his fifth quarter-final of the season when he faces Argentina star Del Potro, who fought for just over three hours to win his opening match on Wednesday. Matosevic improved his record to 16-17 this season with his win over wildcard Thiem, who was the final chance for the host nation at the Stadthalle following the exit of two-time champion and fourth seed Jurgen Melzer. \"I played well against a tough opponent, he had the crowd on his side and I needed to concentrate,\" said Matosevic after his win over Thiem, the world 394. \"I\'m glad to win and am looking forward to a test against Del Potro. He\'s been serving unbelievably but I\'m ready for a tough match.\" Matosevic has already made a breakthrough this week, ending a six-match losing streak when he beat sixth-seeded Dutchman Robin Hasse in the opening round. Slovenia\'s Grega Zemlja shattered Australian hopes of seeing two players in the quarter-finals when he defeated Matthew Ebden 7-5, 6-4.