Czech Petra Kvitova has beaten titleholder Agnieszka Radwanska in straight sets in the Dubai tennis Championships to set up a semi-final against Caroline Wozniacki.
Italian Roberta Vinci will play compatriot and doubles partner Sara Errani in the other semi after beating Samantha Stosur.
Kvitova, the 2011 Wimbledon champion, had not won a match during two previous appearances in Dubai but despite producing 38 unforced errors in the tie she proved too powerful for her Polish opponent.
