Radwanska beat Bulgaria’s Tsvetana Pironkova 6-2 3-6 7-6 (7/5) on Friday to make the last four but owned up to a slice of luck with victory confirmed by a net cord in her favour.
“I was lucky in the match point,” Radwanska told the official tournament website.
“I am happy to win a match that my opponent competed well for.
“Previously I won doubles with my sister (Agnieszka) in Istanbul and my sister had won singles too.
“I have had so many good memories and I want to add more when I am leaving.”
Radwanska will meet Magdalena Rybarikova in the semi-final after the Slovakian fought back to beat Italy’s Roberta Vinci 0-6 7-5 6-2.
Lesia Tsurenko overcame her fellow Ukrainian Kateryna Bondarenko 7-6 (13/11) 7-5 victory in a marathon match which lasted nearly two-and-a-half hours and now meets Belgium’s Kirsten Flipkens, who eased past Francesca Schiavone 6-2 6-4.