Valve plug for fluid connector system and fluid connector system

The invention relates to a valve plug for a fluid connector system and the fluid connector system. A fluid connector system includes first and second valve assemblies that are coupleable together to form a fluid path therethrough and that can prevent fluid flow through the connector system when the valve assemblies are separated from each other, the first valve assembly including a post forming a fluid passage, the second valve assembly including a second valve assembly that forms a fluid passage through which fluid flow through the connector system is blocked when the valve assemblies are separated from each other. The second valve assembly includes a valve plug positioned within the bore and configured to block the fluid passage such that when the valve assemblies are disengaged, the slit of the valve plug prevents fluid flow therethrough, and when the valve assemblies are coupled together, the post extends through the compressible valve, and engagement of the ridge of the valve plug against the post preven