a secondary data storage system for a host computer system includes a disk drive system having a device controller , at least a first magnetic disk and a read / write magnetic transducer positionable with respect to a recording surface of each magnetic disk . a write operation exposes data on adjacent tracks to potential damage if an off track condition occurs to the transducer during a write . a method for controlling write operations through the device controller provides backup of data in tracks adjacent to a target track for the write operation prior to the write operation occurring . the method detects occurrence of events resulting in an off track condition of the magnetic transducer relative to a target track . occurrence of such an event triggers a determination of damage to the contents of tracks adjacent to the target track and restoration of those tracks . write operations to the target track are blocked until shock events discontinue .