The Italian third seed broke twice as she dominated the first set but the second set was more even as the players swapped breaks.

However, Paolini, who lost to Iga Swiatek at Roland Garros earlier this month, stepped up a gear in the tie-break, winning the first seven points to seal victory.

"Today, I played a really good match," Paolini said in her on-court interview.

"She's a really good player on grass, of course she's British, so it's tough to beat her here, especially. I'm happy, I'm enjoying the grass here in Eastbourne."

Boulter, ranked 32nd in the world, came to Eastbourne in good form after retaining her Nottingham Open crown earlier this month.

Canadian world number 30 Leylah Fernandez advanced to her first semi-final of the season, defeating Britain's Harriet Dart 6-2, 6-1.

Fernandez will face defending champion Madison Keys, after Karolina Muchova withdrew from their quarter-final, for a place in the final.

Britain's Emma Raducanu, who beat Fernandez in the 2021 US Open final, was beaten 6-2, 6-2 by Daria Kasatkina.

In the men's competition, Britain's Billy Harris continued his fairytale grass-court season, beating Flavio Cobolli 6-7(3), 7-6(4), 6-2.

Harris, who reached his first quarter-final last week at Queen's, until recently travelled to tournaments, and slept, in a converted van.

Australian qualifier Max Purcell beat Serbia's Miomir Kecmanovic in straight sets, with top seed Taylor Fritz defeating Juncheng Shang in the final quarter-final.