The view of some theorists in the field of SLA is that comprehension practice is essential for establishing strong form-meaning links in the underlying linguistic system and that language production will invariably result from these representations, entailing that output need not be the focus of grammar instruction (VanPatten, 2004). Others hold that language production is a skill which must be developed separate from comprehension (DeKeyser, 1997) and that output can actually directly contribute to the grammar learning process (Swain, 1985; 1995). These opposing views have resulted in several studies contrasting the effects of comprehension and production practice for the initial learning of different language features (e.g., VanPatten & Cadierno, 1993; DeKeyser & Sokalski, 1996). However, Shintani, Li, & Ellis’ (2013) meta-analysis on the relative benefits of comprehension and production practice concluded that both are effective in promoting the development of receptive and productive abilities. The question has thus moved beyond which type of practice is more beneficial for acquisition to how the benefits of each type of practice can be exploited in different learning contexts. Of particular interest is the potential of combining comprehension and production practice in an instructional sequence. Based on theories of skill acquisition (DeKeyser, 2007), the output hypothesis (Swain, 1985; Izumi, 2003) and attention (Gass, 1997), as well as the results of prior research (Tanaka, 1999, 2001; Izumi, 2002), the present study hypothesized that combining the two types practice would lead to learning gains over an instructional sequence, and that alternating the two practice types would be more effective than delaying production for the development of both receptive and productive grammar knowledge. Fourteen12-15 year old Japanese learners of English received instruction on the regular simple past (e.g., walked, cleaned) in four one-hour lessons. The delayed group (n=7) received two session of comprehension practice followed by two sessions of production practice; the alternating group (n=7) received alternating comprehension and production practice sessions. In a time series design, gains in perception and production of the –ed past were measured at three points in time. Repeated measures ANOVAs demonstrated that both groups improved significantly over the course of the treatment and that both early and delayed production practice were equally effective (no interaction between Time and Group). The results thus point to the benefits of using both comprehension and production practice to promote the learning of second language grammar. The discussion of the findings includes pedagogical implications as well as research design modifications for future investigations of optimal combinations of input-based and output-based instruction to best benefit L2 grammar acquisition.