Previous research has used time to stabilization (TTS) from forward landing tasks to assess dynamic postural stability in ACL reconstructed (ACLR) athletes in order to identify impaired sensorimotor control and mechanical stability. This may not be an appropriate test due to the fact that research has suggested that ACL injury has a multi-planar mechanism of injury. The purpose of the present study was to compare TTS values from a forward land and a diagonal land to determine if diagonal landing TTS values are more sensitive to dynamic postural stability deficits in female ACLR athletes.A group of ACL reconstructed female athletes and a group of female control athletes performed three forward lands and three diagonal lands onto a force-plate and remained still on one foot for 15s. TTS was calculated for the anterior-posterior and medial-lateral ground reaction forces as well as the resultant vector of both forces.All three TTS values were significantly increased in the ACLR group from the control group for the diagonal landing task. There was no difference in TTS values between the groups for the forward landing task.TTS values from a diagonal landing are more sensitive at detecting impaired dynamic postural stability in a group of female ACLR athletes compared to TTS values from a forward land.III - Casecontrolled study.