Former world number one Martina Hingis reached the final of the injury-hit Montreal Cup when Russian Anna Chakvetadze was forced to retire in the second set on Saturday.
Hingis won the first set 6-3 and was leading 3-1 in the second when the unseeded Chakvetadze pulled out with an arm injury.
The seventh-seeded Swiss next faces ninth-seeded Russian Dinara Safina or number 13 Ana Ivanovic of Serbia & Montenegro, whose semi-final was suspended by rain.
Ivanovic was leading 6-1, 3-4 when the rain started. The players briefly returned to the court when it stopped, but just before play was to resume the rain started falling again.
The match will be completed on Sunday morning before the final.
"You don't want to win a match like this," Hingis told reporters. "I just hope she gets better before the U.S. Open (which starts on Aug. 28)."
Chakvetadze was the seventh player to withdraw or fail to complete a match in the tournament.
Booing was heard in the crowd at Uniprix Stadium after the 19-year-old told the umpire she could not continue.
"I'm really sad because I knew I could be in the final," Chakvetadze said.
"I wish I could I could play to the end and I just couldn't. I hope it will be okay (for the U.S. Open)."
Hingis said she felt sorry for her opponent.
"I know how I feel when I'm hurting," Hingis said. "When you're facing someone who is not 100 percent, you get nervous too, sometimes you try to do too much.
"I wasn't the freshest either after having played last night, I felt I didn't have that much energy. I managed somehow, I'm in another final here and I'm really happy about that."
Hingis again showed her shot-making ability to keep her opponent off balance, breaking serve four times.
The Russian was twice treated by a trainer at courtside in the first set and was clearly in discomfort for most of the match.
Hingis, who won this event in 1999 and 2000, will be making her third appearance in a final since her returning to tennis following a three-year absence.
