The acquisition of verbal morphology presents challenges for many second language (L2) learners, in part because they do not readily process those forms during sentence comprehension. Instead, L2 learners rely on lexical-semantic cues (e.g., temporal adverbs and explicit subjects). This study investigated the role of task-essential training in changing learners' processing tendencies and tested whether such changes were related to increased performance with the L2 Spanish present, preterite, and future tenses and first- and third-person morphology. The experiment compared a no-training control group to three groups of learners who completed a multisession task-essential training following the principles of structured input (SI). Groups varied in the type of feedback they received. Results of a cue-reliance assessment indicated that each SI group relied significantly more on verbal inflections after training while the control group did not. Furthermore, the extent to which groups relied on verbal inflections on posttest measures correlated moderately to strongly with performance on interpretation and written production measures. Implications are discussed for input processing, learned attention, and pedagogy, in particular the impact of feedback on cue reliance and learning outcomes.