Method for separating a volume of whole blood into at least a plasma component and a red blood cell component comprising centrifuging a separation bag containing a volume of whole blood so as to separate therein at least a first component comprising plasma and a second component comprising red blood cells； transferring the first component into a plasma component bag during centrifugation of the separation bag； transferring into the separation bag a volume of wash solution from a wash solution bag during centrifugation of the separation bag； mixing the volume of wash solution with the second component； centrifuging the separation bag so as to separate therein a washed red blood cell component and a supernatant component； and transferring the supernatant component into a waste bag during centrifugation of the separation bag.
