As a part of the discussion about how movement knowledge is valued in physical education teacher education (PETE), issues of assessment have been brought to the fore. Studies have shown that how and when movement knowledge is assessed is strongly culturally dependent and based different epistemological orientations. The aim of this paper is to analyse and discuss how preservice teachers in Sweden perceive assessment in an invasion games course according to the games performance assessment instrument (GPAI). The empirical material presented in this study is based on a web-survey carried out at the end of the invasion games course where the participants were asked to write comments of how the experienced GPAI and its relevance in school physical education. The findings suggest that the preservice teacher experience prediction and measurement of appropriate and non-appropriate behaviours in GPAI as problematic from a didactic perspective. The ideas of “correctness” and “appropriateness”, which are fundamental in GPAI, is discussed in the relation to the socially critical constructivist epistemology that underpins Swedish PETE.