A disk drive is disclosed comprising a disk having a plurality of tracks,
wherein each track comprises a plurality of data sectors and a plurality
of servo sectors. The disk drive further comprises a head actuated over
the disk, the head comprising a read element radially offset from a write
element by a reader/writer offset. In order to rewrite a marginal servo
sector detected in a target track, control circuitry within the disk
drive relocates user data recorded in a first data sector of a near
adjacent track to a staging memory. Servo data is written over the first
data sector, and the read element is used to read the servo data written
over the first data sector to actuate the head to rewrite the marginal
servo sector of the target track. The user data stored in the staging
memory is then rewritten to the first data sector.