Three-time defending champion Iga Swiatek secured a dominant 6-2, 7-5 victory over Elena Rybakina to reach the semi-finals of the Qatar Open, while Russia’s Ekaterina Alexandrova upset American sixth seed Jessica Pegula.

In a repeat of last year’s final, second seed Swiatek made a strong start on Thursday, breaking Kazakhstan’s fifth seed Rybakina in her opening service game to take a 2-0 lead, before breaking again to wrap up the first set with ease.

Rybakina, who recently learned that the WTA had upheld a ban on her former coach Stefano Vukov following a code of conduct investigation, responded well in the second set, breaking in the opening game.

However, Swiatek, showing great intensity, fought back to level the score at 4-4 and delivered the decisive break while Rybakina was serving to force a tie-break.

"I'm super happy and proud of myself because playing against Elena is never easy," said Swiatek.

"At the beginning of the second set, she really raised her level, so I had to do the same in order to fight back."

Rybakina had previously led their head-to-head record 4-3, but Swiatek now progresses to face the winner between Tunisia’s Ons Jabeur and Latvia’s Jelena Ostapenko.

Elsewhere, Pegula, a US Open finalist last year, claimed the first set, but the in-form Alexandrova, who had already stunned top seed and world number one Aryna Sabalenka in the second round, fought back to win 4-6, 6-1, 6-1.

Alexandrova, now on an eight-match winning streak, will take on either Ukraine’s Marta Kostyuk or American Amanda Anisimova in the semi-finals.

"I'm really happy with the way I'm playing right now," said Alexandrova.

"I want to keep this form going as long as possible, no matter what."