Social interaction between humans takes place in the spatial environment on a daily basis. We occupy space for ourselves and respect the dynamics of spaces that are occupied by others. In human-robot interaction, spatial models are commonly used for structuring relatively far-away interactions or passing-by scenarios. This work instead, focuses on the transition between distant and close communication for an interaction opening. We applied a spatial model to a humanoid robot and implemented an attention system that is connected to it. The resulting behaviors have been verified in an online video study. The questionnaire revealed that these behaviors are applicable and result in a robot that has been perceived as more interested in the human and shows its attention and intentions earlier and to a higher degree than other strategies.