at the Union Buildings in Pretoria
Berlin - Former world number one Kim Clijsters retired from the German Open on Thursday after being troubled by a right leg injury during a third-round match against Switzerland's Patty Schnyder.
Clijsters failed to convert four match points before surrendering the match while leading 7-6 5-6.
The Belgian had won four of her five previous encounters with Schynder, currently ranked 13th in the world.
Clijsters has been on the comeback trail after missing the second half of last season and the first three months of this year with a wrist injury.