A flying start sent Govortsova on her way to a 6-1, 6-3 victory, which she wrapped up after a fraction over an hour on court.
Two years ago Diatchenko left the Taiwanese capital with the title, but since then injuries have seen her career stall. The Russian's hopes of regaining the title suffered an early setback as she dropped her opening two service games. It was a blow she was unable to recover from, Govortsova confidently wrapping up the opening set, then rattling off six of the final seven games to close out victory.
"It was important that I started well; I knew she'd hot a hard, heavy ball and that I'd have to be aggressive," Govortsova said. "Even though the score was 6-1, I still had to concentrate on every single ball and I played really well today.
"I've been playing singles and doubles, every day since Monday, so I'm used to the courts now and feel in pretty good shape."
In the semifinals, Govortsova will face another Russian, No.6 seed Evgeniya Rodina, whose own quarterfinal against Ashleigh Barty was cut short. Having lost the first set, 6-1, Rodina was leading 3-0 in the second when the Australian retired with an abdominal injury.
"It was tough today because I didn't feel confident and I felt a little bit tired," Rodina said. "She played very good in the first set, but in the second set I tried to play more my type of tennis and it worked. I don't know what happened with her - she felt some pain and retired."
On the other side of the draw, Chang Kai-Chen will face Marina Erakovic. Chang produced a strong finish against Luksika Kumkhum, winning the final five games to triumph, 6-1, 7-5, while Erakovic saw off Tatjana Maria, 6-4, 7-6(4), in Friday's final match.