Abstract: We discuss mesons in thermalizing gluon backgrounds in the N=2 SQCD using the gauge/gravity duality. In the gravity dual we realize the thermalization by the black hole formation, using a spatially-homogeneous injection of energy. For this purpose, we choose the geometry of the bulk to be the Vaidya-AdS geometry. We consider the dynamics of a probe D7-brane in this geometry and discuss three kinds of brane embeddings which are possible in this setup, depending on the final temperature and the time scale of the energy injection. Two of these embeddings, called Minkowski and black hole embedding, are the same as the case of statics backgrounds and one, called overeager, is new for dynamical case. We discuss about a numerical computation of this problem, and specially focus our attention the case where the final temperature is sufficiently low to have Minkowski embedding.