Cancer diagnosis prototypically represents a critical life event and, thus, requires extensive coping efforts by the patients which may be promoted by support received from their social network members. Quantity and quality of received support can be determined by the patients' self-presentation of their coping behavior ("coping-portrayal") and by their attempts at mobilizing support. Until now, research has indicated that a depressive and ruminative coping-portrayal may especially evoke negative emotional reactions in others. The quasi-experimental study presented here focused on the effects of a ruminative coping-portrayal on willingness of others in providing social support and investigated, in particular, if these effects may be counteracted by more or less direct attempts at support mobilization. A sample of 189 middle-aged subjects received fictitious descriptions of an encounter with a "former schoolmate" (protagonist) who discloses that he has recently been diagnosed with cancer. The protagonist's directness of support mobilization (explicit vs. implicit vs. no request of support) as well as his coping-portrayal (with vs. without rumination) were systematically manipulated. Action tendencies with regard to sustained support (e.g., high time-investment) and short-term encouragement as well as the intensity of specific emotions (e.g., sympathy; fear of one's own distress; joy at the other's trustfulness) were considered as dependent variables. Results showed that a ruminative coping-portrayal evoked less sympathy than a coping-portrayal without rumination; moreover, a ruminative way of presenting one's coping behavior induced action tendencies which were described by momentary encouragement rather than by sustained support endeavors. Explicit requests of support reduced subjects' fear of their own distress and mostly increased joy at the protagonist's trustfulness compared to implicit requests. Furthermore, the negative effects of a ruminative coping-portrayal on the subjects' willingness to provide sustained support were compensated by explicit requests for support provision. In general, these results quite convincingly show that the way of activating supportive actions from others can be crucial for support received when facing a critical life event.