The governance of sport refers to decisions that are made at the constitutive level, specifically (from p. 205 in Lasswell and McDougal 1991) :
[C]onstitutive decisions ... establish and maintain the community's most comprehensive process of authoritative decision. These are the decisions, it may be recalled, that establish and characterize authoritative decision makers, state and specify basic community policies, establish appropriate institutional structures, allocate bases of power to the different institutional structures, authorize procedures for the making of different types of decision, and secure the performance of all the different types of decisions necessary to clarifying and securing common interest and effectuating community policy.In contrast, governance in sport refers to decisions that are made within the constitutive frameworks, and can be simply thought of as decisions related to what happens on the pitch, court, ice, etc.
Most attention is paid to the governance in sport, understandably -- Should Torres be included on the Euro 2012? Who should manage England? Is a 4-4-2 preferable to a 3-5-1-1? These are decisions that involve the implementation of sport. However, the implementation of sport is only possible because of the larger constitutive processes. Every sports fan cares deeply about governance in sport, but what they may not know is the critical importance which sport depends upon effective mechanisms of governance of sport.