An unexpected mechanistic switch as well as a change of the product distribution in the thermal gas‐phase activation of methane have been identified when diatomic [ZnO].+ is ligated with acetonitrile. Theoretical studies suggest that a strong metal–carbon attraction in the pristine [ZnO].+ species plays an important role in the rebound of the incipient CH3. radical to the metal center, thus permitting the competitive generation of CH3., OH., and CH3OH. This interaction is drastically weakened by a single CH3CN ligand. As a result, upon ligation the proton‐coupled single electron transfer that prevails for [ZnO].+/CH4 switches to the classical hydrogen‐atom‐transfer process, thus giving rise to the exclusive expulsion of CH3.. This ligand effect can be modeled quite well by an oriented external electric field of a negative point charge.