Graduate Teaching Assistants (GTAs) carry a substantial instructional role in introductory courses for many mathematics and statistics departments. As a result, many GTAs have first-hand influence on the initial statistical impressions of students from a range of disciplines. But as simultaneous learners of the discipline themselves, GTAs in statistics are still forming their conceptions of statistics and statistics instruction. Using multiple case study design, I conducted a longitudinal study with four, first-year statistics GTAs aimed at capturing their experiences and notions related to statistics. This paper highlights several important disciplinary perspectives and tensions expressed by the GTAs. In addition to examining their disciplinary notions, I also discuss noteworthy connections between the participants' statistical perspectives and their pedagogical views for introductory statistics. Findings reveal that the participants struggled to reconcile how authentic statistical practice could be translated into the introductory curriculum. Implications for GTA training are discussed.