British wildcard Katie Boulter recorded the biggest win of her career with an epic victory against world No 2 Elena Rybakina to reach the HSBC Championships semi-finals at the Queen's Club.

With a 7-5 2-6 7-5 upset of top seeded Rybakina, world No 73 Boulter advanced to the final four and will face Croatia's Donna Vekic in Saturday's semi-finals.

The win over Rybakina marked Boulter's second of the day with her second-round match against Jaqueline Cristian being pushed to Friday morning because of rain on Thursday.

Boulter prevailed against the Romanian 6-3 6-1 before ousting Rybakina, who came through a tough battle with reigning champion Tatjana Maria 6-7 (4-7) 7-5 6-0, for her second top five win on the WTA Tour.

"Honestly, I am not really sure what to say. I really feel like this win goes to the crowd that got me through it tonight and stayed out here," Boulter told BBC Sport.

"I just tried to keep backing myself and go for it. If you don't go for it, you're going to regret the things you've worked so hard for."

Boulter added: "I'm standing here a winner because I trusted my game, I trusted my team. I'm so proud of today.

"My first semi-final here, it's a really special one. I'm wanting more so I'm going to keep pushing and get myself ready for tomorrow."

Vekic is into her second tour-level semi-final of 2026, and has made the most of her opportunity as a lucky loser.

She earned a spot in the main draw after Marta Kostyuk pulled out with an ankle injury, and Vekic now has a chance to reach her first tour-level final since Bad Homburg in 2024.

Fellow Briton Emma Raducanu could potentially also have to play two matches in the same day after reaching the quarter-finals earlier on Friday.

She clinched a place in the quarter-finals for a second straight year after securing a 6-4 6-2 win over Romanian Sorana Cirstea.

Raducanu's last-eight match against lucky loser Kamilla Rakhimova was originally scheduled to be last on Andy Murray Arena on Friday, but because of the length of the previous four matches, it has now moved to Saturday.

Home hope Raducanu could face Iva Jovic in the semi-finals if she wins her clash with Rakhimova, scheduled for 12.30pm.

The 18-year-old upset No 2 seed Amanda Anisimova, the 2025 Wimbledon runner-up, 6-2 3-6 6-3 to secure the first top five victory of her career.

"Every match I feel more confident on the grass," Jovic said afterwards. "I have to keep working on my serve, my return -- the first couple of shots in the point are super important on grass. But it's trending in the right direction. Just stacking up the matches."

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