[en] Coherent control of internal conversion (IC) between the first (S₁) and second (S₂) singlet excited electronic states in pyrazine, where the S₂ state is populated from the ground singlet electronic state S₀ by weak field excitation, is examined. Control is implemented by shaping the laser which excites S₂. Excitation and IC are considered simultaneously, using the recently introduced resonance-based control approach. Highly successful control is achieved by optimizing both the amplitude and phase profiles of the laser spectrum. The dependence of control on the properties of resonances in S₂ is demonstrated. (paper)