A fresh gas supply device for an internal combustion engine having an exhaust gas turbocharger includes a charge air inlet for letting in compressed charge air from the exhaust gas turbocharger; an outlet connected to the charge air inlet, wherein the connection is closable via at least one backflow flap pivotable about a rotational flap axis; a compressed air inlet for letting compressed air into the outlet; an adjusting unit for adjusting the at least one backflow flap; at least one additional turbocharging unit having an air turbine and a compressor coupled thereto. The air turbine is disposed upstream of the compressed air inlet in the flow direction of the compressed air and compressed air can flow through the air turbine. The compressor is designed to take in and compress additional charge air from the charge air inlet and deliver compressed additional charge air to the outlet.