Although the development of implicit grammatical knowledge is highly desirable, not all grammatical constructions could be learned implicitly. Therefore, one of the ultimate objectives of most English as Foreign Language (EFL) classrooms is to aid learners in developing their (automatic) explicit grammatical knowledge. Using progressively complex tasks and task-supported instructional conditions is one efficient way to materialize this objective. The current study investigates the extent to which performing focused dictogloss tasks accompanied with explicit instruction (EI) affects EFL learners’ explicit knowledge and automatized explicit knowledge of the past-counterfactual conditional structure. Sixty-seven upper-intermediate proficiency learners were assigned into four groups: task performance without any EI (Task- Only); prewriting EI (Pre-EI); prewriting EI also available during task enactment (Pre + online- EI); and post-writing EI with revision (Post-EI). Results indicated explicit knowledge gains for the Pre-EI and Pre + online-EI groups in the immediate and delayed posttests. However, no significant development appeared concerning the automatized explicit knowledge. Learners’ task engagement and the discrepancies and correspondences between the learning outcomes and learners’ and teachers’ perceptions are further discussed.