In a typical serial reaction time task developed by Nissen and Bullmer (1987), acquisition of the event sequence is assessed by verbal reports and performance change with a repetition of fixed serial pattern. Eimer, Goschke, Schlaghecken, and Sturmer (1996) reported that when one item of a repeatedly presented 10-item sequence was replaced by a deviant item, knowledge of sequence was reflected in a faster reaction times for standard compared with deviant items and in an enhanced ERP negative component for deviant items. In this experiment, sequence learning with deviant stimuli in a serial reaction time task was evaluated with and without a concurrent tone-counting task. The results showed that the shorter and less repetitive sequence compared to Eimer et al. (1996) replicated their effects in performance measures. This confirmed the validity of a deviant-stimulus-paradigm and usefulness of psychophysiological measures to evaluate explicit and implicit aspects of and the role of attention in sequence learning.