The electrical resistivity of single-crystal Rb3C60 has been measured
in magnetic fields up to 7.0 T. A substantial broadening of the resist
ive transition to the superconducting state is observed and attributed
to the combined effects of magnetofluctuations near T(c) and thermall
y activated flux creep dominant at lower temperatures. We evaluate cha
racteristic parameters for Rb3C60 crystals including the upper critica
l field H(c2)(T), the scattering time tau, coherence length xi, and me
an free path l; these are contrasted to similar parameters determined
previously for K3C60.