Juan Martin del Potro beat Gilles Muller in the semi-finals of the Erste Bank Open in Vienna

Juan Martin del Potro: Finalist again in Vienna

Juan Martin del Potro will be hoping to go one better than last year after reaching his second successive final in Vienna.

The 24-year-old Argentinian, who lost to Jo-Wilfried Tsonga in the Erste Bank Open final last year, overcame a determined Gilles Muller of Luxembourg 7-6 (7-4) 7-6 (7-5) in the last four.

The match consisted mainly of short rallies and featured no breaks of serve.

Del Potro converted his fourth match point with his 17th ace, while Muller sent down 16 aces.

The top seed will now play Grega Zemlja of Slovenia, who shocked second-seeded Serb Janko Tipsarevic 3-6 7-6 (7-5) 6-2, in Sunday's final.

Del Potro, the 2009 US Open champion, is playing his first tournament since returning from a wrist injury that sidelined him for more than a month.

"Being in a final means a lot for me after a month without playing. I'm showing a good level, but I still need to improve," he said.

"Break points were almost like set points. If you miss one you are under pressure. The difference today was that I played better in the tiebreaks."

World No 70 Zemlja trailed 3-1 in the second set but hit back strongly to reach his first ATP Tour final.

"This is an incredible dream," said Zemlja. "I am full of confidence now.

"Only in the third set I started thinking about winning. I got the feeling the match was in my hands but it was hard work and I had to stay focused until the last point."

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