This article presents the implementation of the Video Assistant Referee (VAR) as an example of the increasingly layered mediatization of sports. We argue that, while integrated into the established broadcasting protocols, VAR becomes an object of explicit reflection and popular debate—and increasingly so, when football and its TV coverage are discussed on “technologies of engagement” like Twitter. Combining the concept of mediatization with insights from Science and Technology Studies, this article discusses how and why sports systematically contribute to what we call “mediatized engagements with technologies.” The combination of football’s “media manifold” comprising epistemic technologies, television, and social media with its knowledgeable and emotionally invested audience inevitably limits the “black-boxing” of a refereeing technology. Our case study analyses how fans, journalists, and others evaluate VAR in action on Twitter during the men’s 2018 FIFA World Cup. Based on a multilingual dataset, we show, among other examples, how the media event displays the technology as a historical innovation and analyze why even the allegedly “clear and obvious” cases of its application create controversies. In conclusion, the article discusses how the layered mediatization of sports, its partisanship, and ambivalent relationship with technologies stimulate engagement far beyond the fair refereeing issue.