Was the original disk actually "failed" or still online showing a "predicted failure"? Do you have OMSA installed?  If not, what OS are you running? In OMSA, go to Storage, PERC, Information/Configuration (link at top of page), then Rescan from the dropdown menu of Available Tasks for the controller.
Have a PowerEdge 2800 with a pair of virtual discs on the PERC 4.  One RAID 1 array and one RAID 5 array.  One of the discs on the R5 showed up as degraded, lit up a SMART error in the logs, and started physically blinking on the chassis.  Ordered a replacement drive, hot-swapped it, and it immediately began rebuilding.  2 hours later, went to 100% without any errors.  The Virtual Disc lists itself at "Ready" with a green checkmark.  However... if I click on it and view the physical discs contained in the virtual disc, the same member disc shows as "Degraded".  In the Event Viewer I have an Event 2124 "Redundancy normal:  Virtual Disk 1 (Virtual Disk 1) Controller 0 (PERC 4e/Di)" and Event 2092 "Array disk Rebuild completed:  Array Disk 1:9 Controller 0, Channel 1".  A good sign, to be sure, but I'm still worried about this replaced disc showing as degraded.  Any clues?
PERC 4e/Di disk replacement - still shows "Degraded"