Katie Boulter set to be reinstated as British No.1 following Japan Open semi-final run

Katie Boulter has reinstated herself as the British No.1 following a 3-6, 6-3, 6-3 win over Antonia Ruzic in the quarter-finals of the Japan Open.

She had returned to being the top British player following her slump in 2025, winning the Ostrava Open with a return to form evident. She has been steady throughout much of this season, but another promising display in Japan has taken the headlines in the UK and will result in a big move in the rankings.

Ruzic was the player in command in the early stages. She sprinted out into a 3-0 lead before Boulter managed to get on the board. She broke back to make it 3-4 before Ruzic seized back the initiative, serving it out to lead.

The Croatian led by a set and a break, but Boulter would up the gears from here. She came out on top in a trio of consecutive breaks to level at 3-3 before winning the final three games to force a decider. The 30-year-old led 4-0 before Ruzic got one of the breaks back. Boulter stayed firm and got the job done with a break to love.

"[Ruzic] is a really good player, full credit to her," Boulter said following the victory. "I tried to hang tough and find a way. I was a bit lucky in the middle of the second [set] but I feel I did really well to stay there."

She will face Katerina Siniakova after the doubles specialist thrashed Mary Stoina 6-1, 6-2. “She's one hell of a player, extremely dangerous. It's going to be who gets the first strike in. I've got nothing to lose. She's been building extremely well this week, so I'm going to have to come prepared."

The other semi-final will be contested between American duo Ann Li and Ashlyn Krueger for a spot in the final in Osaka.

Boulter is on the rise following this run in the WTA 250 event. She was recently overtaken by the outstanding Sonay Kartal after her return from injury. She made it to the final of the Wuhan Open after being ranked 170th in the world but lost to Maja Chwalinska. This saw her climb all the way to World No.49 after climbing 121 places.

Boulter is set to reclaim that coveted spot in British tennis. The former World No.23 is set to rise to 48th in the world, with Kartal moving outside the top 50 thanks to results around her. Boulter can still move up further with more wins in Osaka. She will be the World No.44 if she makes the final, with a title boosting her another spot to 43rd.

Emma Raducanu began the year as the British No.1, but her slide down the order has resulted in her now being the fourth highest ranked British player on the WTA Tour. Francesca Jones is also ahead of her with Harriet Dart closing in.