Emma Raducanu has suffered another injury setback after being forced to retire mid-match from her Korea Open quarter-final against Daria Kasatkina.
Raducanu had shown promising signs during her two victories in the tournament, battling hard to beat top-50 players Peyton Stearns and Yue Yuan on her way to a last-eight showdown with the top seed.
The 21-year-old received treatment on her foot during her victory over Yuan but had been given an extra day to recover ahead of her clash with Kasatkina, after heavy rain in Seoul forced play to be abandoned on Friday and pushed the quarter-finals to Saturday.
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Kasatkina breezed through the opening set 6-1 in just over 30 minutes against an out-of-sorts Raducanu, who then retired ahead of the second set to give the world No 13 a place in the last four.
"First of all, I feel sorry for Emma for retiring during the match," Kasatkina said. "It's a pity to get injured, especially in the deeper stages on the tournament. I wish her a speedy recovery to get ready for the next tournament. I know that this swing is important for her."
Raducanu struggles with injury in Korea
The 21-year-old was looking to make her second WTA Tour semi-final this year, having also reached the last four in Nottingham in June, but struggled against an opponent who had beaten her in straight sets in both previous encounters.
Raducanu recovered from losing the opening game on her serve to immediately break back in the next, although struggled on her serve again as Kasatkina won the third game to move ahead.
The former US Open champion lost the next two games and received physio on her left foot ahead of the sixth, where she showed signs of discomfort after being broken to love.
Kasatkina then held in the next to close out the set, which was enough for victory when Raducanu decided to retire. Raducanu will now be hoping to be fit for the China Open, a WTA 1000 event beginning on Wednesday.
Elsewhere, 2017 runner-up Beatriz Haddad Maia reached the semi-finals with a 6-2 6-1 win over Polina Kudermetova and Veronika Kudermetova defeated Viktoriya Tomova 7-5 6-3.
What's coming up on Sky Sports Tennis in September?
- Korea Open - WTA 500 (September 16-22)
- Thailand Open - WTA 250 (September 16-22)
- Chengdu Open - ATP 250 (September 17-24)
- Hangzhou Open - ATP 250 (September 18-24)
- Japan Open - ATP 500 (September 25-October 1)
- China Open - ATP 500 (September 26-October 2)
- China Open - WTA 1000 (September 25-October 6 - with Emma Raducanu in action)
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