In recent years, a considerable amount of research has been conducted to delineate the effects of attentional focus on task performance (e.g., Wulf, 2007a). From this research, external focus has been shown to be beneficial to both motor learning and performance. Less clear, however, are the mechanisms through which external focus benefits performance (Poolton, Maxwell, Masters, & Raab, 2006). Traditionally, an information-processing perspective (e.g., common-coding theory) has suggested that external focus facilitates performance by triggering associated sensorimotor representations responsible for motor production (Wulf & Prinz, 2001). More recently, however, a constraints-led perspective has suggested that external focus aids performance by strengthening action-perception coupling through facilitating attunement to environmental affordances (Davids, Button, & Bennet, 2008). Consequently, the purpose of the present study was to delineate between a common-coding account and a constraints-led perspective regarding the beneficial role of external focus of attention. More specifically, the extent to which visual information underpins the advantage of external focus was examined. The study examined skilled golfers (n = 30) on a putting task under one of three attentional focus conditions (control, irrelevant, and external). Additionally, participants performed under full and occluded vision. Putting performance was measured via both outcome- and process-oriented approaches. Results from the present study indicated that visual information did not mediate the extent to which external focus impacted performance. Regardless of the availability of visual information, performance during external focus resulted in a greater number of successful putts. Furthermore, analyses of movement trajectory variability indicated that the degree of variability reduced from the start of the forward swing to the point of contact. Variability during external focus resulted in moderate levels of variability compared to the control and irrelevant focus conditions. Overall, results lend support to a common-coding account of external focus.