Victoria Azarenka's performances in reaching the semi-finals of the WTA Championships in Istanbul have been so impressive that many believe she will emerge as the main challenger to Caroline Wozniacki's world No 1 ranking.
The Belarussian will climb two places to No 2 if she wins the title Sunday, which makes it remarkable to recall that earlier this year she said she was through with the sport and wanted to give up professional tennis.
Disappointing losses to Daniela Hantuchova, in Doha, and Flavia Pennetta, in Dubai, combined with a tendency to be over-emotional about defeat, had blinded her at the age of 22 to her considerable potential.
It required kindness from her family to help her get over those powerful emotions. And professional counselling helped her consolidate that change into a better structured working attitude.
Part of that Azarenka now describes as "trying not to care too much if I lose. I'm just here to do the best I can ... By not caring I mean just not creating such a big drama out of losing.
"If you lose, you lose. It's not the end of the world. And we're here playing tennis, being able to do something we love. So why make a big deal out of it?"
It helps that the resolution to her emotional crisis has happened at a time on the WTA Tour when the Williams sisters are no longer dominant, when Justine Henin and Kim Clijsters have left the game for a second time, and when there are more opportunities to succeed than for a very long time.
"With so many champions out, it seems the opportunity is quite open," she said.
At St Petersburg, Russia, Janko Tipsarevic and Alex Bogomolov Jr maintained their good form with both advancing to the semi-finals of the St Petersburg Open on Friday.
Second-seeded Tipsarevic rallied to beat Potito Starace 6-7, 6-2, 6-1.
Seventh-seeded Bogomolov beat Serbian qualifier Dusan Lajovic 6-2, 6-1. It is the second time this year that Bogomolov has reached a semi-final. He also made the final four in Los Angeles in June.