Heat-assisted magnetic recording (HAMR) disk drive and method for writing

A heat-assisted magnetic recording (HAMR) disc drive has a laser, a near field transducer coupled to the laser and a rotatable disc. The disc has a recording layer with concentric or spiral data tracks, servo sectors SS extending across the tracks, a laser power gap LPG adjacent each servo sector, and data sectors DS between the laser power gaps and the servo sectors. The servo sector SS-START preceding the first data sector to be written and the servo sector following the last data sector SS-END to be written are identified. Any old data in the data sectors between said first and last servo sectors is acquired, and the old and new data is combined. The laser is turned on when the laser power gap adjacent the first servo sector rotates past the transducer. The combined old and new data is then written in all of the data sectors continuously between said first and last servo sectors. The laser power gap allows the laser power to stabilize prior to writing to the data sectors with a write head.