Can rsync redirect extraneous source files to a separate folder

I use an external hard disk to sync selected folders regularly for backup.
Is it possible in rsync to redirect any files that are not present in the 'source' directory to a different folder (which is outside the 'destination' directory hierarchy).
In all any files that are not in the 'source' directory,
1. should not be left in the 'destination' directory
2. should not be deleted from the 'destination', instead redirected to a separate folder.

Thanks