Jelena Jankovic has reached the semi-finals of the BNP Paribas Open after her opponent Lesia Tsurenko was forced to retire in the second set through injury.

The Ukrainian injured her ankle during her victory over Eugenie Bouchard earlier in the tournament, and it gave out again in the quarter-finals after just 46 minutes.

After Tsurenko lost the first set 6-1, her trainer wrapped up her ankle in an attempt to get her through the contest, but she withdrew during the second set with Jankovic leading 4-1.

Jankovic will take on either defending champion Flavia Pennetta or 24th-seeded Sabine Lisicki in the semi-finals at Indian Wells.