Former world number one Victoria Azarenka saved three match points before winning on her comeback from a year out after the birth of her son.
The two-time Australian Open champion, who gave birth to Leo in December, won 6-3 4-6 7-6 (9-7) against Japan's Risa Ozaki at the Mallorca Open.
It was the 27-year-old Belarusian's first match since losing at the French Open in June 2016.
Azarenka was sixth in the world when she announced her pregnancy last July.
She was a game away from defeat when play was suspended on Tuesday because of fading light.