The wake of a sphere rolling along a wall at low Reynolds number is investigated numerically and experimentally. Two successive transitions are identified in this flow, as the Reynolds number is increased. The first leads to the periodic shedding of planar symmetric hairpin vortices. The second and previously unknown transition involves a loss of planar symmetry and a low-frequency lateral oscillation of the wake, exhibiting a surprising 7:3 resonance with the hairpin vortex shedding. The two transitions are characterized by dye visualizations and quantitative information obtained from numerical simulations, such as force coefficients and wake frequencies (Strouhal numbers). Both transitions are found to be supercritical. Further increasing the Reynolds number, the flow becomes progressively more disorganized and chaotic. Overall, the transition sequence for the rolling sphere is closer to the one for a non-rotating sphere in a free stream than to that of a non-rotating sphere close to a wall.