Abstract: A network- and/or client-side media content replacement system/service (“MCRS”) facilitates identification and replacement of media content on media content players when defects associated with the media content players could negatively affect play of the media content. In one exemplary scenario, a media content player transmits a first message, which uniquely identifies the original media content item, to a network-based MCRS. It is determined based on the first message whether a defect associated with the media content player could negatively affect play of the original media content item, and if it is determined that play of the original media content item may be negatively affected, an alternate media content item is identified (for example, via a second message transmitted from the MCRS) to replace at least a portion of the original media content item.