This work is part of a wider investigation aiming to explore and describe the process of teaching combinatorics in Italian secondary schools both from the point of view of teachers’ knowledge, practices and relations with the spontaneous strategies that students develop during combinatorial problem solving. In this work we will focus on a pilot study conducted with a group of pre-service teachers - as part of the whole research process - whose solving strategies and combinatorial reasoning were analysed under the lens of two different analytic tools. We present the results of this analysis together with a reflection on the two constructs used aiming to develop an instrument of analysis that would take into account both statical and dynamical aspects of combinatorial problem solving.