A composition of matter is disclosed wherein the composition comprises: A) at least one latent mercaptosilane coupling agent; and B) at least one additional mercaptan. Preferably, the composition comprises: A) at least one sulfur vulcanizable rubber; B) at least one latent mercaptosilane coupling agent; C) at least one latent mercaptosilane activator; D) at least one filler; and, optionally, E) at least one additional mercaptosilane. A two pass process for preparing cured articles, such as tires and/or tire treads, which employs the composition is also disclosed.