the describers performed an exact cladistic analysis to determine its phylogenetic position. the outcome of the phylogenetic analysis placed "blasisaurus" as the sister taxon to "arenysaurus". together they form a clade that is higher in lambeosaurinae than "tsintaosaurus" and "jaxartosaurus". whether this clade was more derived than "amurosaurus", the closest relative of the group, was not determined. however, one study did find that they were not sister taxa, no other studies supported this. "blasisaurus" confirmed the hypothesis that in the late cretaceous, different hadrosaurids from asia and europe was a sign that they migrated across land bridges that must have been present. where in lambeosaurinae "blasisaurus" and "arenysaurus" fall is disputed. they have been found to be in lambeosaurini, as basal to the lambeosaurini-parasaurolophini split, and in parasaurolophini. below is the most recent cladogram published including "blasisaurus" and "arenysaurus", found by penélope cruzado-caballero "et al." in 2013: