diff --git a/v3/internal/assetserver/fallback_response_writer.go b/v3/internal/assetserver/fallback_response_writer.go
index cd5a5d9e3..c26d3cc52 100644
--- a/v3/internal/assetserver/fallback_response_writer.go
+++ b/v3/internal/assetserver/fallback_response_writer.go
@@ -71,3 +71,10 @@ func (fw *fallbackResponseWriter) WriteHeader(statusCode int) {
 
 	fw.rw.WriteHeader(statusCode)
 }
+
+// Flush implements the http.Flusher interface.
+func (rw *fallbackResponseWriter) Flush() {
+	if f, ok := rw.rw.(http.Flusher); ok {
+		f.Flush()
+	}
+}