Abstract. It has been suggested by Dvali et al. that certain derivatively coupled non-renormalizable scalar field theories might restore the perturbative unitarity of high energy hard scatterings by classicalization, i.e. formation of multiparticle states of soft quanta. I will discuss our recent work where we apply the semiclassical method of calculating the multiparticle production rates to the scalar DBI theory which is suggested to classicalize. We find that the semiclassical method is applicable for the energies in the final state above the cutoff scale of the theory L_*^(-1). We encounter that the cross section of the process two to N ceases to be exponentially suppressed for the particle number in the final state N smaller than a critical particle number N_{crit} ~ (E L_*)^(4/3). It coincides with the typical particle number produced in two-particle collisions at high energies predicted by classicalization arguments.