Former world number one Martina Hingis was defeated in the semi-finals of her comeback tournament on Friday when she lost 1-6, 7-6, 6-2 to Italian Flavia Pennetta at the Australian hardcourt championships.
Hingis, who retired in 2002 with foot and ankle injuries, showed glimpses of the skills that took her to five Grand Slam titles but faded after romping through the first set.
The 25-year-old Swiss said she had strained a hip-flexor muscle towards the end of the second set forcing her withdrawal from a doubles semi-final later on Friday.
"As a player and a competitor you try to overcome things like that and still play until the end of the match," Hingis told reporters about the hip injury.
"I don't want to take anything away from Pennetta, she played a great match.
"I was able to compete with her. It was great tennis and everyone enjoyed it.
"You can't always expect everything to be perfect with your body when you haven't done that much in three years.
"If I was to evaluate this tournament right away, I'm very happy and very positive about what I've achieved this week.
"I don't think anybody expected me to come out like this, so it's pretty good."
Pennetta will now meet Lucie Safarova in the final after the Czech teenager beat third-seeded Dinara Safina 6-4, 6-2 in the earlier semi-final.
Safarova had already disposed of sixth seed Ai Sugiyama in the first round and top seed Patty Schnyder in the quarter-finals.