A radio-frequency transmission device for a magnetic resonance system to generate magnetic resonance exposures of an examination region of an examination subject, has: a first radio-frequency transmission antenna that emits radio-frequency signals in the examination region, a radio-frequency amplifier that supplies the first radio-frequency transmission antenna, with radio-frequency signals with a predetermined radio-frequency transmission power, and a second radio-frequency transmission antenna fashioned to label a medium flowing in the examination region and/or examination regions via emission of labeling radio-frequency signals, such that the medium can be identified in the generated magnetic resonance exposures of the examination region. The second radio-frequency transmission antenna is coupled with the radio-frequency amplifier to supply the first radio-frequency transmission antenna, such that it likewise supplies the second radio-frequency transmission antenna with radio-frequency signals with a predetermined radio-frequency transmission power for the emission of radio-frequency labeling signals.