PurposeIn response to increasing competition for consumer attention, sport governing bodies have innovated short-format, action-oriented versions of traditional sports to attract new fans. This article explores how sport governing bodies (SGBs) manage the need for innovations to both conform to existing stakeholder expectations whilst offering novel benefits in comparison to competition (i.e. legitimate distinctiveness).Design/methodology/approachCreated by the English Cricket Board (ECB), The Hundred competition was used as a case study to explore the conformity-differentiation tension through a legitimacy lens using document and media analysis.FindingsSeven themes were created to explain how the ECB managed legitimacy tensions: rule modification, team creation, scheduling, game-day experience, broadcasting, gender equity and sponsorship. In each theme, differentiation and conformity were traded-off by the ECB to prioritise pragmatic legitimacy with broadcasters and sponsors.Practical implicationsFor sport management professionals, the Hundred demonstrates the commercial value of differentiating new sporting events from competitors via hybrid broadcasting partnerships, embedded gender equity and designing game-day experiences that attract hard-to-reach consumer demographics.Originality/valueSGBs must trade-off legitimacy between sources when innovating to survive, and when faced with conflicting expectations, commercial imperatives determined whether to conform or differentiate.