The former top-ranked Muster, who turns 44 early next month, made his comeback to professional tennis last year after 11 years away.
"You should not drag it along forever," Muster said Wednesday. "I wanted to relive competitive tennis again and I've really enjoyed it." Muster is ranked 847th after winning two matches in 18 tournaments on the lower-tier Challenger tour. He has lost both his main-draw matches at ATP level.
"Vienna will definitely be my last appearance in an ATP event," said the Austrian, who was No. 1 for six weeks in 1996. "Maybe I play a few Challengers next year, but that will be it." Tournament director Herwig Straka has confirmed that Muster will be awarded a wild card for the Erste Bank Open, beginning Oct. 22.
Muster first played in the Vienna event 27 years ago, reaching the final three times but failing to win the tournament.
"I've made good progress this year but my age is counting," Muster said. "For me, I know what's still possible if I put even more effort into it. But I have a family and also would get to my physical limits one day." Muster became the only Austrian to win a Grand Slam event when he lifted the French Open trophy in 1995. He is his country's most successful player ever after winning 44 titles.
He never formally retired from professional tennis but said in 1999 he would "go on a holiday." By then, Muster had already staged a remarkable comeback.
His career was almost ruined when he severely damaged his left knee in a car accident before the final of the 1989 Key Biscayne tournament. He was back on tour less than six months later.