[en] Using the diabatic ground state H⁺₃ surface given in analytic form by Giese and Gentry, a coupled-states study of the rotational excitation of H₂ (taken as a rigid rotor) by proton impact is made at 3.7 eV. Transitions 0→j', with j'=0,2,4,...,26, are considered, and one finds a broad distribution in final rotor state j' which is consistent with recent beam experiments. Despite long-range rotational coupling produced by the charge-quadrupole interaction, the coupled-states method gives a good description of the rotational excitation process as is demonstrated by comparison to standard close-coupling cross sections. Intermultiplet transitions (neglected in the coupled-states approximations) are shown to be less important in the high energy limit