Vienna - French top seed Jo-Wilfried Tsonga survived against hyped-up local wildcard Dominic Thiem to reach the Austrian Open semi-finals with a 6-4, 3-6, 7-6 (7/3) win Friday.
Tsonga, winner of the 2011 title, saw his 20-year-old opponent, ranked 149 in the world, save a match point in the third set.
The victory took nearly two and a quarter-hours as Tsonga stayed on course to secure one of the four remaining spots in the season-ending ATP World Tour Finals next month.
Tsonga ended with 16 aces but had to save seven break points against Thiem, who was facing his first top 10 opponent.
"He was a young guy playing in front of his home crowd with nothing to lose," said Tsonga.
"I had to fight and stay strong.
"My game was pretty poor from the baseline but I served well. I'm a top 10 player and it's my job to win matches like this. Experience made the difference at the end."
Tsonga will Saturday play Dutchman Robin Haase, who recovered to beat third seed Fabio Fognini 6-7 (4/7), 6-1, 6-1 as the colourful Italian faded away after winning a tight opening set.
Germany's Tommy Haas also reached the semis, beating one Czech Davis Cup player only to find himself facing a second one in the next round.
Second-seeded Haas, the 2001 champion, spent one and three-quarter hours in holding off fifth seed Radek Stepanek, a member of his nation's 2012 Davis Cup championship side, 7-6 (12/10), 6-3.
The 35-year-old Haas will next take on eighth-seeded Czech Lukas Rosol, who beat Belgian Ruben Bemelmans 6-3, 1-6, 6-3 in his quarter-final.
Haas, also chasing a place in the World Tour Finals, stayed in touch on provisional 12th as he booked his place in the final four.
The one-time world number two won the 63-minute opening set against Stepanek only after saving four set points and converting on his own second chance.
With the opening set in the bag, Haas then got to work to finish off the job against his 34-year-old opponent, breaking for 4-2 in the second set and advancing on his first match point.
"Winning the tiebreaker was crucial," said Haas. "I was a little bit lucky to win that set. It came down to a few points and who just had the luck at the moment, who was slightly better in the end."
Haas has never faced Rosol, who famously knocked Rafael Nadal out of Wimbledon in 2012.