Disk drive to enable defect margining

A disk drive to enable defect margining during disk drive burn-in testing comprising:

• a disk comprising a plurality of tracks;
• a head actuated over the disk;
• and
• a processor to:
• perform disk drive burn-in testing to detect media defects;
• generate an initial defect list based upon detected media defects for sectors;
• generate an extended defect list that includes detected media defects and extended defect margins from the detected media defects;
• determine whether the extended defect list or the initial defect list is to be utilized for burn-in;
• and
• utilize either the extended defect list or the initial defect list for burn-in based on a result of the determination, wherein a spare area of the disk allows for the detected media defects and the extended defect margins when the extended defect list is utilized.