Recently, Morse has proposed a new adaptation scheme (so-called "high-order tuner") which generates as outputs not only tuned parameters, but also their time derivatives up to a certain order. In this paper a robustified variant of the high-order tuner is introduced to adaptively stabilize a SISO linear plant subjected to external disturbances. In comparison with Morse＇s tuner, the proposed one has essentially simplified structure. Namely, the total order of time-varying auxiliary filters is reduced 2n times (where n is the order of the plant to be controlled).