VIENNA -- His passion for tennis renewed, 43-year-old Thomas Muster plans to resume his comeback next season.
Muster, once ranked No. 1, lost Tuesday in his first match on the ATP Tour after 11 years away. He was beaten by 23-year-old Andreas Haider-Maurer 6-2, 7-6 (5) in an all-Austrian match in the first round of the Bank Austria Trophy.
The result means Jimmy Connors remains the oldest player to win on the ATP Tour. At 42, Connors reached the quarterfinals in Halle, Germany, in 1995.
Muster won the French Open in 1995 and became No. 1 the next year. He returned to competitive tennis on the second-tier Challenger circuit in June before accepting a wild card for the Vienna tournament.
"I'll keep training hard and plan to enter 20 to 25 events from March," Muster said.
"There is no pressure of getting into the top 10," he said. "It's about enjoying tennis. In '99, I hated tennis. Now I love it."
Muster had been drawn to face Ernests Gulbis in the first round before the 24th-ranked Latvian pulled out Monday for personal reasons.
"I am relieved despite losing as I gave my best and played pretty well," Muster said. "A third set would have been great, but well done to Andreas."
Before a capacity crowd of 8,700 at the Stadthalle, Muster dropped serve in the opening game and struggled throughout the first set, failing to pressure his 157th-ranked opponent.
Muster, who won 40 of his 44 career titles on clay, could not find the timing on his groundstrokes on the fast indoor hard court. He did save four break points to take the second set to a tiebreak but hit a forehand wide on Haider-Maurer's second match point.
"There was more in it if I could have played more aggressively in the first set," Muster said. "In the second, I managed to dictate the pace of the game sometimes. I served better and I became more active."
Earlier, James Blake of the United States lost 6-4, 6-4 to Lukasz Kubot of Poland in the first round. Kubot broke his seven-match losing streak and will next face top-seeded Jurgen Melzer of Austria, the defending champion.
Germany's Michael Berrer upset sixth-seeded Guillermo Garcia-Lopez 6-3, 4-6, 7-5. The 29th-ranked Spaniard, who won in Bangkok and reached the quarterfinals in Tokyo and Shanghai this month, double-faulted 12 times. Berrer will play Pablo Cuevas of Uruguay, who defeated Thiemo de Bakker of the Netherlands 7-6 (6), 1-6, 6-4. Eighth-seeded Juan Ignacio Chela of Argentina defeated Andrej Martin of Slovakia 6-3, 6-3.
Also, Tobias Kamke defeated fellow German Matthias Bachinger 6-4, 6-4; Santiago Geraldo of Colombia stopped Xavier Malisse of Belgium 6-4, 1-6, 6-1; and Grega Zemlja of Slovenia rallied past Marsel Ilhan of Turkey 4-6, 6-1, 7-5.