Systems and methods are provided for improving the flow rate of plasma being removed from a blood separation chamber during a blood separation procedure. The system includes a blood separation chamber in which plasma is separated from cellular blood components and an outlet line for removing the separated plasma from the blood separation chamber. A primary optical sensor assembly is associated with the blood separation chamber to directly monitor the interior of the blood separation chamber. A secondary optical sensor assembly is associated with the outlet line to monitor the separated plasma in the outlet line, with each optical sensor assembly checking for the presence of cellular components in the separated plasma. If the primary optical sensor assembly detects such a condition while the secondary optical sensor assembly does not, then a controller may take steps to resolve the conflict and continue the procedure.