Katie Boulter has reclaimed the British No 1 ranking from Sonay Kartal after advancing to the semi-finals of the Japan Open in Osaka.

Boulter produced a comeback victory over Croatia’s Antonia Ruzic to reach her third semi-final of the season, where she will face Katerina Siniakova.

Boulter trailed Ruzic by a set and a break early in the second, but won 11 of the next 13 games to turn the match around.

Ruzic, the world No 91, broke back as Boulter served for the match, but the Briton steadied to seal a 3-6, 6-3, 6-3 win in almost two hours.

Kartal had risen to No 50 in the world after her stunning run to the biggest final of her career at the Wuhan Open, a WTA 1000 event, last week.

But Boulter’s run in Osaka means she will now re-enter the world’s top 50, rising to at least No 48 in the rankings ahead of tomorrow’s semi-final.

The 30-year-old Boulter will play the Czech world doubles No 1 Siniakova, who has a singles ranking of No 86, in the semi-finals.

Boulter, the eighth seed in Japan, had previously reached the semi-finals of Queen’s in June while she won the title in Ostrava back in February.

The other semi-final in Osaka, which is a WTA 250 tournament, is the all-American clash between top seed Ann Li and Ashlyn Krueger.