British players always seem to thrive at the HSBC Championships (Queen's Club Championships). Maybe it's the heavy grass court, maybe it's the magic of Andy Murray Arena. Either way, Katie Boulter used the homecourt advantage to her favor against second-ranked Elena Rybakina on Friday afternoon. Boulter defeated Rybakina in a hard-fought, three-setter: 7-5, 2-6, 7-5.It was Boulter's second top-five victory and the biggest win of her career. Even more impressively, it was both players' second match of the day. Rain resulted in a doubleheader for Boulter and Rybakina on Friday. Rybakina squeezed past Tatjana Maria earlier in the day: 6-7(4), 7-5, 6-0. Katie Boulter's Upset VictoryON HER HOME TURF‼️@katiecboulter defeats the No.1 seed Rybakina in a thrilling three set battle, and books her ticket into the semifinals. #HSBCChampionships pic.twitter.com/ZTnH1bzTfN— wta (@WTA) June 12, 2026The match lasted 2 hours and 39 minutes, and could have easily gone the other way. Rybakina served at a higher rate, hit more winners, and had fewer unforced errors. However, Boulter came through in the clutch. Rybakina was 2/13 in break point opportunities, compared to Boulter's 2/7 break points.Boulter shook her head in disbelief after eliminating the one-seed. She credited the home crowd during her breathless on-court interview, and the local fans erupted in cheers of "Let's go, Katie." Unfortunately, the loss was just the beginning of a bad day for Rybakina. Elena Rybakina's Deactivated Instagram— Sebastien G. (@sebsharfam2) June 12, 2026Tennis fans on Reddit pointed out that Rybakina deactivated her Instagram account after the loss. This comes just a few weeks after she turned off the comments following her first-round exit at Roland-Garros. It's a disappointing loss for Rybakina, who is trying to close the gap on WTA World No. 1 Aryna Sabalenka. Rybakina is still the World No. 2, but falls to 32-9 after today's defeat.It is safe to assume that Rybakina took a break from social media to escape the verbal abuse of fans and gamblers. This is an all-too-common issue among tennis players — especially women. Last June, the WTA and ITF issued a report revealing that gambling-related anger fueled a majority of online threats.Katie Boulter's Next MatchWHAT IT MEANS! 👏@katiecboulter | #HSBCChampionships pic.twitter.com/tugCkR3g28— wta (@WTA) June 12, 2026Boulter entered the tournament as a wild card and has now picked up three consecutive wins. The World No. 73 improves to 19-11 on the year and will face Donna Vekić in the semifinals on Saturday. Last year, Boulter upset the nine-seed Paula Badosa in the first round of the Wimbledon Championships. So far, she is gearing up for an even better grass campaign this year.On the other side of the draw, Iva Jovic awaits the winner of Emma Raducanu and Kamilla Rakhimova in the semifinal. Stay locked into Sports Illustrated's Serve On SI for all of your tennis news from the court and beyond.Add us as a preferred source on GoogleFollow